Logical Reasoning

A comprehensive Civil Service Exam reviewer covering Logical. Designed to test critical thinking with detailed explanations for Medium level questions. Time limit: 30 minutes.

Question 1

A sequence of numbers is presented: 3, 7, 13, 21, 31, ___. What number logically completes the sequence?

  • 39
  • 41
  • 43
  • 45
Explanation:

The pattern involves adding increasing even numbers to the previous term. The differences between consecutive numbers are: 7-3=4, 13-7=6, 21-13=8, 31-21=10. Following this pattern, the next difference should be 12. Therefore, 31 + 12 = 43.

Question 2

All successful entrepreneurs are innovative. Some innovative individuals are risk-takers. Therefore, which of the following statements must be true?

  • Some successful entrepreneurs are risk-takers.
  • All innovative individuals are successful entrepreneurs.
  • Some risk-takers are innovative.
  • No successful entrepreneurs are risk-takers.
Explanation:

Let S be successful entrepreneurs, I be innovative individuals, and R be risk-takers. We are given: 1) All S are I (S is a subset of I). 2) Some I are R (There is an overlap between I and R). From these premises, we know that successful entrepreneurs are a subset of innovative individuals. There is an overlap between innovative individuals and risk-takers. However, we cannot definitively conclude anything about the direct relationship between successful entrepreneurs and risk-takers. It is possible that the innovative individuals who are risk-takers are also successful entrepreneurs, but it is not a certainty. The only statement that *must* be true from 'Some innovative individuals are risk-takers' is its converse: 'Some risk-takers are innovative'.

Question 3

Five students, A, B, C, D, and E, are sitting in a row. C is to the immediate right of A. B is to the immediate left of D. E is not at either end of the row. If A is not at either end of the row, and D is not next to A, what is the exact order of the students from left to right?

  • B A C E D
  • E A C B D
  • B D A C E
  • A C E B D
Explanation:

Let's deduce the positions step-by-step for a 5-person row (P1 P2 P3 P4 P5): 1. C is to the immediate right of A: This means 'A C' sequence. 2. B is to the immediate left of D: This means 'B D' sequence. 3. E is not at either end (P1 or P5). 4. A is not at either end (P1 or P5). 5. D is not next to A. From (3) and (4), A and E must be in positions P2, P3, or P4. Consider the 'A C' block. Since A is not at an end, A can be P2 or P3 (if A were P4, C would be P5, which is an end, but A itself cannot be P5). So, A can be P2 or P3. Let's try placing A at P2: _ A C _ _ Since E cannot be at P1 or P5, E must be at P4. This gives: _ A C E _ Now we need to place 'B D'. The remaining positions are P1 and P5. To maintain 'B is to the immediate left of D', B must be at P1 and D at P5. This gives the order: B A C E D. Let's check all conditions for B A C E D: - C is to the immediate right of A: Yes (A at P2, C at P3). - B is to the immediate left of D: Yes (B at P1, D at P5). - E is not at either end: Yes, E is at P4. - A is not at either end: Yes, A is at P2. - D is not next to A: Yes, D is at P5 and A is at P2. They are separated. All conditions are met. So, the order is B A C E D.

Question 4

GLOVE : HAND :: SHOE : ____

  • SOCK
  • LEG
  • FOOT
  • LACE
Explanation:

A glove is an item worn on a hand. Similarly, a shoe is an item worn on a foot.

Question 5

Which word does not belong to the group?

  • Optimistic
  • Hopeful
  • Pessimistic
  • Positive
Explanation:

Optimistic, Hopeful, and Positive all convey a positive outlook or expectation. Pessimistic means having a negative outlook, making it the antonym and the odd one out.

Question 6

A, C, F, J, O, ____. What is the next letter in the sequence?

  • S
  • T
  • U
  • V
Explanation:

The pattern involves adding an increasing number of letters between consecutive terms in the alphabet: A (+2 letters) C C (+3 letters) F F (+4 letters) J J (+5 letters) O Following this pattern, the next step should be O (+6 letters). Counting 6 letters after O (P, Q, R, S, T, U) leads to U.

Question 7

Prolonged exposure to loud noises can damage hearing. Frequent use of headphones at maximum volume is a common practice among teenagers. Therefore, it is likely that:

  • Teenagers prefer loud music.
  • Hearing loss among teenagers will increase.
  • Headphones are inherently dangerous.
  • Teenagers will avoid loud noises in the future.
Explanation:

The premises establish a cause-and-effect relationship: loud noises cause hearing damage. The second premise states that teenagers frequently engage in the cause (loud noises via headphones). The logical conclusion is that the effect (hearing loss) will likely increase among this group. While teenagers might prefer loud music (a), that's not a direct consequence of the premises. Headphones are not inherently dangerous (c), but their misuse is. Teenagers avoiding loud noises (d) is a hopeful outcome, not a likely consequence of current behavior.

Question 8

A company decided to launch a new product line targeting millennials. The marketing team assumed that social media advertising would be the most effective way to reach this demographic. Which of the following is an underlying assumption made by the marketing team?

  • Millennials prefer new products.
  • Social media is the primary source of information for millennials regarding new products.
  • The new product line will be successful.
  • Traditional advertising methods are ineffective for millennials.
Explanation:

For social media advertising to be considered the 'most effective way' to reach millennials, the marketing team must be assuming that millennials primarily use social media as their main source of information, especially for new products. If they used other channels more, social media wouldn't be the *most* effective. Option (a) is a general preference, not specific to advertising. Option (c) is a desired outcome, not an assumption guiding the method. Option (d) is too strong; it might be an implied belief, but (b) is more direct to the 'most effective way' claim.

Question 9

All engineers are logical thinkers. Some artists are logical thinkers. Based on these statements, which of the following is a valid conclusion?

  • Some engineers are artists.
  • All logical thinkers are engineers.
  • No artists are engineers.
  • None of the above conclusions can be drawn with certainty.
Explanation:

Let E = engineers, L = logical thinkers, A = artists. 1. All E are L (E is a subset of L). 2. Some A are L (A and L have an overlap). From these, we know that the group of engineers is entirely contained within the group of logical thinkers. We also know that some members of the artist group are also logical thinkers. However, we cannot make any definitive statements about the relationship between engineers and artists. Some artists might be engineers, some might not. Options (a), (c), and (d) are not necessarily true. Option (b) is false because not all logical thinkers are engineers (some are artists). The premises do not *force* any of the specific relationships between artists and engineers to be true. Therefore, none of the provided conclusions are necessarily valid.

Question 10

1, 4, 9, 16, 25, ____. What is the next number in the sequence?

  • 30
  • 36
  • 40
  • 42
Explanation:

This is a sequence of perfect squares: 1^2=1, 2^2=4, 3^2=9, 4^2=16, 5^2=25. The next number in the sequence would be 6^2 = 36.

Question 11

A city is experiencing a significant increase in traffic congestion during peak hours, leading to longer commute times and increased air pollution. Which of the following measures would be the *most effective* long-term solution?

  • Adding more lanes to existing highways.
  • Encouraging carpooling through incentives.
  • Investing in and expanding public transportation systems.
  • Implementing a congestion pricing scheme for private vehicles.
Explanation:

1. Adding more lanes to existing highways (a) often provides only temporary relief, as it can induce more traffic demand in the long run (induced demand). 2. Encouraging carpooling through incentives (b) can help but might not be sufficient to address significant, systemic congestion. 3. Implementing a congestion pricing scheme (d) can be effective in reducing demand in specific areas but may shift traffic to other routes or create equity issues. 4. Investing in and expanding public transportation systems (c) offers a sustainable and comprehensive long-term solution. By providing viable alternatives to private vehicles, it reduces the overall number of cars on the road, decreases reliance on individual vehicles, and is generally more environmentally friendly. This addresses the root cause of too many individual vehicles for the existing infrastructure.

Question 12

If A is the brother of B, B is the sister of C, and C is the father of D, how is D related to A?

  • Father
  • Nephew
  • Uncle
  • Niece/Nephew
Explanation:

1. A is the brother of B. 2. B is the sister of C. This means A, B, and C are siblings. 3. C is the father of D. Since C is D's father, and A is C's sibling, A is D's uncle. D is A's niece or nephew (gender not specified, so 'niece/nephew' or 'child of sibling' is the relationship from D's perspective). The question asks how D is related to A, meaning D is A's niece or nephew.

Question 13

"Our new product is clearly superior because it's the best-selling item in its category." Which logical fallacy is most implicitly present in this statement?

  • Ad Hominem
  • Appeal to Popularity (Bandwagon)
  • Straw Man
  • Slippery Slope
Explanation:

The statement claims superiority based solely on popularity ('best-selling'). This is an example of the 'Appeal to Popularity' or 'Bandwagon' fallacy, which suggests that something must be good, true, or superior because many people believe it or like it.

Question 14

Imagine a square piece of paper is folded in half vertically, then folded in half horizontally. A small hole is punched through the center of the folded paper. When the paper is unfolded, how many holes will be visible?

  • 1
  • 2
  • 3
  • 4
Explanation:

1. Folding in half vertically creates 2 layers of paper. 2. Folding in half horizontally again creates 4 layers of paper. When a hole is punched through the center of this folded paper, it passes through all 4 layers simultaneously. Upon unfolding, each of these layers will reveal a hole. Since the punch was in the 'center' of the folded paper, it means it's one hole in the middle of each of the four quadrants of the original paper, resulting in 4 distinct holes.

Question 15

A recent study suggests that consuming dark chocolate regularly improves cognitive function in adults. Researchers concluded that dark chocolate should be recommended as a dietary supplement for brain health. Which of the following, if true, would *most strengthen* the researchers' conclusion?

  • The study was conducted on a diverse group of participants.
  • Other studies have shown that milk chocolate has no effect on cognitive function.
  • The improvements in cognitive function observed were statistically significant and sustained over time.
  • Dark chocolate contains antioxidants known to benefit overall health.
Explanation:

The conclusion is a recommendation based on observed improvements. To strengthen this, we need evidence that the improvements are robust and meaningful. (a) A diverse group strengthens generalizability, but not necessarily the *degree* or *sustainability* of the effect. (b) Comparing to milk chocolate is useful for differentiation but doesn't directly strengthen the positive claim about dark chocolate. (c) If the improvements are statistically significant (meaning unlikely due to chance) and sustained over time, this provides strong evidence for the effectiveness and long-term benefit of dark chocolate, directly supporting the recommendation for brain health. (d) Knowing the mechanism (antioxidants) is good scientific practice but doesn't, by itself, prove the *observed cognitive benefit* or its sustainability.

Question 16

2, 5, 11, 23, 47, ____. What is the next number in the sequence?

  • 91
  • 93
  • 95
  • 97
Explanation:

The pattern is (Previous number × 2) + 1: 2 × 2 + 1 = 5 5 × 2 + 1 = 11 11 × 2 + 1 = 23 23 × 2 + 1 = 47 Following this pattern, the next number is 47 × 2 + 1 = 94 + 1 = 95.

Question 17

WHEEL : CAR :: PAGE : ____

  • PAPER
  • READ
  • BOOK
  • WORD
Explanation:

A wheel is a fundamental component or part of a car. Similarly, a page is a fundamental component or part of a book.

Question 18

Consider the following statements: I. All dogs are mammals. II. Some mammals are pets. III. My pet is a dog. Which of the following conclusions can be drawn from these statements?

  • All dogs are pets.
  • Some pets are not mammals.
  • My pet is a mammal.
  • All mammals are dogs.
Explanation:

Let's analyze the statements: I. All dogs are mammals (Dogs ⊆ Mammals). II. Some mammals are pets (Mammals ∩ Pets ≠ Ø). III. My pet is a dog. From statement III, 'My pet is a dog', and statement I, 'All dogs are mammals', we can logically deduce that 'My pet is a mammal'. If my pet is a dog, and all dogs fall into the category of mammals, then my pet must also be a mammal.

Question 19

A restaurant owner decided to install security cameras, believing it would deter theft and improve employee accountability. What is the fundamental assumption the owner made?

  • Employees are inherently dishonest.
  • The presence of cameras will change behavior.
  • Theft is a major problem in the restaurant.
  • Security cameras are affordable.
Explanation:

For security cameras to deter theft and improve accountability, the owner must assume that the presence of these cameras will be noticed and will influence the behavior of potential thieves and employees. That is, people will act differently because they know they are being watched. Option (a) is too strong; it's about deterrence, not inherent dishonesty. (c) might be true, but it's the *reason* for the cameras, not the assumption about their *effectiveness*. (d) is about practicality, not the underlying logic of the policy.

Question 20

A series of shapes changes as follows: a square, then a circle, then a triangle, then a square. What shape comes next in the sequence?

  • Triangle
  • Square
  • Circle
  • Rectangle
Explanation:

The sequence is a repeating pattern of three shapes: Square, Circle, Triangle. After the second square, the pattern restarts, so the next shape will be a Circle.

Question 21

To determine the average speed of a car, which of the following information is sufficient?

  • The distance traveled and the time taken.
  • The car's maximum speed and the number of stops.
  • The car's acceleration and its starting speed.
  • The type of fuel used and the engine size.
Explanation:

Average speed is defined as the total distance traveled divided by the total time taken. Therefore, knowing these two pieces of information is sufficient to calculate the average speed. The other options provide irrelevant or insufficient information for calculating average speed.

Question 22

Arrange the following events in a logical chronological order: 1. Graduation from university 2. Enrollment in elementary school 3. Birth 4. Retirement from work 5. High school completion

  • 3, 2, 5, 1, 4
  • 2, 3, 5, 1, 4
  • 3, 5, 2, 1, 4
  • 3, 2, 1, 5, 4
Explanation:

The logical chronological order of these life events is: 3. Birth (first event in life) 2. Enrollment in elementary school (typically after birth, as a child) 5. High school completion (after elementary school) 1. Graduation from university (after high school) 4. Retirement from work (typically after a career following university) So the correct sequence is 3, 2, 5, 1, 4.

Question 23

A local government proposes building a new bypass road to alleviate traffic congestion in the city center. They argue that this will significantly reduce travel times for commuters. Which of the following, if true, would *most weaken* their argument?

  • The construction of the bypass will be very expensive.
  • Studies show that new roads often lead to increased urban sprawl.
  • The bypass will primarily serve through-traffic, not local commuters.
  • Public transportation use has been declining in the city for years.
Explanation:

The government's argument is that the bypass will reduce travel times for *commuters*. If the bypass primarily serves *through-traffic* (vehicles passing through the city without stopping, not those commuting to or within the city center), then it would do little to alleviate congestion for local commuters. This directly undermines the stated benefit of the bypass for commuters. Options (a), (b), and (d) describe potential negative side effects or unrelated issues but do not directly challenge the claim that the bypass would reduce commuter travel times.

Question 24

No birds are mammals. All cats are mammals. Based on these statements, what can be concluded?

  • All birds are cats.
  • No cats are birds.
  • Some mammals are birds.
  • All mammals are cats.
Explanation:

Let's use Venn diagrams or set theory: 1. 'No birds are mammals' means the set of birds and the set of mammals are entirely separate (disjoint). 2. 'All cats are mammals' means the set of cats is entirely contained within the set of mammals. Since cats are a subset of mammals, and mammals have no overlap with birds, it logically follows that cats also have no overlap with birds. Therefore, 'No cats are birds' (and 'No birds are cats') is a valid conclusion.

Question 25

If a mirror image of the word "CIVIL" is rotated 180 degrees, what would it look like?

  • CIVIL
  • LICIV
  • LIVIC
  • ƆIV⅃
Explanation:

1. Original word: CIVIL 2. Mirror image: When you look at 'CIVIL' in a mirror, the letters appear reversed (horizontally flipped) and in reverse order from right to left. So, the 'L' is first, then 'I', 'V', 'I', and 'C'. - C becomes Ɔ (reversed C) - I remains I - V remains V - I remains I - L becomes ⅃ (reversed L) So, the mirror image, read from left to right as a word, is ⅃ I V I Ɔ. 3. Rotate the mirror image (⅃ I V I Ɔ) 180 degrees: - ⅃ (reversed L) rotated 180 degrees becomes L. - I rotated 180 degrees becomes I. - V rotated 180 degrees becomes V. - I rotated 180 degrees becomes I. - Ɔ (reversed C) rotated 180 degrees becomes C. Therefore, the final result is L I V I C.

Question 26

Three friends, Alex, Ben, and Chloe, each have a different favorite color: red, blue, or green. 1. Alex does not like red. 2. Ben likes neither green nor red. What is Chloe's favorite color?

  • Blue
  • Green
  • Red
  • Cannot be determined
Explanation:

Let's list the possibilities: Colors: Red, Blue, Green Friends: Alex, Ben, Chloe From statement 2: Ben likes neither green nor red. The only remaining color is Blue. So, Ben's favorite color is Blue. Now we have: Ben = Blue Remaining colors: Red, Green Remaining friends: Alex, Chloe From statement 1: Alex does not like red. Since the only remaining colors are Red and Green, and Alex doesn't like Red, Alex must like Green. Therefore: Ben = Blue Alex = Green Chloe must like the only remaining color, which is Red.

Question 27

"If it rains, then the ground is wet." Which of the following statements is logically equivalent?

  • If the ground is wet, then it rained.
  • If it does not rain, then the ground is not wet.
  • If the ground is not wet, then it did not rain.
  • The ground is wet only if it rains.
Explanation:

This is a conditional statement of the form 'If P, then Q' (P → Q). The only statement logically equivalent to a conditional statement is its contrapositive, which is 'If not Q, then not P' (~Q → ~P). Let P = 'it rains' Let Q = 'the ground is wet' So, ~Q = 'the ground is not wet' And ~P = 'it did not rain' The contrapositive is 'If the ground is not wet, then it did not rain'. Option (a) is the converse (Q → P), which is not logically equivalent. Option (b) is the inverse (~P → ~Q), which is not logically equivalent. Option (d) is 'Q only if P', which means 'If Q then P', same as converse.

Question 28

10, 8, 11, 9, 12, 10, ____. What is the next number in the sequence?

  • 11
  • 12
  • 13
  • 14
Explanation:

This sequence alternates between two operations: 10 (-2) 8 8 (+3) 11 11 (-2) 9 9 (+3) 12 12 (-2) 10 Following this pattern, the next operation should be (+3). So, 10 + 3 = 13.

Question 29

COMPASS : DIRECTION :: THERMOMETER : ____

  • HEAT
  • WEATHER
  • TEMPERATURE
  • METER
Explanation:

A compass is an instrument used to measure or indicate direction. Similarly, a thermometer is an instrument used to measure temperature.

Question 30

A government proposes to increase taxes on sugary drinks to combat rising obesity rates. What is a key assumption underlying this policy proposal?

  • Higher taxes on sugary drinks will significantly reduce their consumption.
  • Obesity is solely caused by the consumption of sugary drinks.
  • The revenue generated from the tax will be used to fund health programs.
  • The public will support the tax increase.
Explanation:

For the tax to be an effective measure to combat obesity, the government must assume that increasing the price of sugary drinks will lead to a significant decrease in their consumption. If consumption doesn't change much, the tax won't achieve its health goal. Option (b) is too strong; sugary drinks are a contributor, not the sole cause. (c) describes a potential use of funds, not an assumption about policy effectiveness. (d) is about public reception, not the policy's mechanism.

Question 31

Which of the following is the odd one out?

  • Circle
  • Square
  • Triangle
  • Sphere
Explanation:

A Circle, Square, and Triangle are all two-dimensional geometric shapes. A Sphere is a three-dimensional geometric shape. Therefore, Sphere is the odd one out.

Question 32

All citizens have the right to free speech. John is a citizen. Therefore, John has the right to free speech. This is an example of:

  • Inductive reasoning
  • Abductive reasoning
  • Deductive reasoning
  • Analogical reasoning
Explanation:

Deductive reasoning starts with a general statement or principle (all citizens have the right to free speech) and moves to a specific conclusion (John, being a citizen, has this right). The conclusion is guaranteed to be true if the premises are true.

Question 33

Z, X, V, T, R, ____. What is the next letter?

  • Q
  • P
  • O
  • N
Explanation:

This is a reverse alphabetical sequence where each letter is two positions before the previous one: Z (-2 letters) X X (-2 letters) V V (-2 letters) T T (-2 letters) R Following this pattern, R (-2 letters) P.

Question 34

A witness states, "The suspect was wearing a red hat and a blue jacket." Later, the same witness states, "I distinctly remember the suspect having no hat." These two statements are:

  • Consistent
  • Contradictory
  • Irrelevant
  • Partially true
Explanation:

The first statement claims the suspect was wearing a red hat. The second statement claims the suspect had no hat. These two claims directly contradict each other. Therefore, the statements are contradictory.

Question 35

In a race, Mark finished ahead of John but behind Peter. Sarah finished ahead of Peter. Who finished last?

  • Mark
  • Peter
  • Sarah
  • John
Explanation:

Let's represent 'finished ahead of' with '>'. 1. Mark finished ahead of John: Mark > John 2. Mark finished behind Peter: Peter > Mark Combining these two: Peter > Mark > John 3. Sarah finished ahead of Peter: Sarah > Peter Combining all: Sarah > Peter > Mark > John Therefore, John finished last.

Question 36

1, 1, 2, 3, 5, 8, 13, ____. What is the next number?

  • 18
  • 20
  • 21
  • 22
Explanation:

This is the Fibonacci sequence, where each number is the sum of the two preceding numbers. 1 + 1 = 2 1 + 2 = 3 2 + 3 = 5 3 + 5 = 8 5 + 8 = 13 Following this pattern, the next number is 8 + 13 = 21.

Question 37

A company observed that its sales increased after launching a new advertising campaign. They concluded that the advertising campaign was successful. What is the most significant flaw in this conclusion?

  • It doesn't consider the cost of the advertising campaign.
  • It assumes that sales would not have increased otherwise.
  • It ignores the possibility that the product quality decreased.
  • It only focused on sales, not customer satisfaction.
Explanation:

The conclusion assumes that the advertising campaign was the *sole* cause of the sales increase. However, many other factors could have contributed to or even been primarily responsible for the sales increase, such as seasonal demand, improvements in the product itself, competitor issues, or overall market growth. Attributing the increase solely to the campaign without considering other variables is a logical flaw (post hoc ergo propter hoc fallacy).

Question 38

ICE : COLD :: FIRE : ____

  • SMOKE
  • BURN
  • HOT
  • ASH
Explanation:

Ice is characterized by its property of being cold. Similarly, fire is characterized by its property of being hot.

Question 39

A scientist observed that a new strain of bacteria thrives in warm, moist environments. Based on this, what is the most logical inference?

  • The bacteria will die in cold, dry conditions.
  • The bacteria is likely to be found in tropical regions.
  • The bacteria can only survive in warm, moist environments.
  • The bacteria is harmless to humans.
Explanation:

If the bacteria *thrives* (grows best) in warm, moist environments, it is most logical to infer that these are the conditions where it will most likely be found in nature. Tropical regions are characterized by warm and moist conditions. Options (a) and (c) are too strong ('will die', 'can only survive'). Option (d) is an unsupported assumption about the bacteria's effect on humans.

Question 40

All members of the chess club are intelligent. Some students are members of the chess club. Therefore:

  • All intelligent people are in the chess club.
  • Some students are intelligent.
  • No intelligent people are students.
  • All students are intelligent.
Explanation:

1. All members of the chess club (C) are intelligent (I). (C ⊆ I) 2. Some students (S) are members of the chess club (C). (S ∩ C ≠ Ø) If there are some students who are in the chess club, and everyone in the chess club is intelligent, then those specific students who are in the chess club *must also be intelligent*. Therefore, 'Some students are intelligent' is a valid conclusion.

Question 41

1, 10, 3, 8, 5, 6, 7, ____. What is the next number?

  • 2
  • 4
  • 8
  • 9
Explanation:

This sequence consists of two interleaved series. Series 1 (odd-positioned terms): 1, 3, 5, 7 (Each term increases by 2) Series 2 (even-positioned terms): 10, 8, 6 (Each term decreases by 2) The next number in the overall sequence is the fourth term of Series 2. Following the pattern of Series 2, 6 - 2 = 4.

Question 42

SCISSORS : CUT :: PEN : ____

  • PAPER
  • INK
  • WRITE
  • BOOK
Explanation:

Scissors are a tool used for the action of cutting. Similarly, a pen is a tool used for the action of writing.

Question 43

Three statements are made: 1. The cat is black. 2. The dog is brown. 3. Either the cat is not black or the dog is not brown. If only one of these statements is true, which animal has which color?

  • The cat is black, the dog is not brown.
  • The cat is not black, the dog is brown.
  • The cat is not black, the dog is not brown.
  • The cat is black, the dog is brown.
Explanation:

Let P = 'The cat is black' and Q = 'The dog is brown'. The statements are: 1. P 2. Q 3. ~P or ~Q (This is equivalent to NOT (P AND Q) by De Morgan's Law) We are told that exactly one of these statements is true. Case 1: Assume statement 1 (P) is true. If P is true, then statement 2 (Q) must be false (since only one statement can be true). So, the dog is not brown. If P is true and Q is false, let's check statement 3: (~P or ~Q) becomes (false or true), which is TRUE. This means if P is true, then statement 3 is also true. This contradicts the condition that *only one* statement is true. So, statement 1 cannot be the only true statement. Case 2: Assume statement 2 (Q) is true. If Q is true, then statement 1 (P) must be false. So, the cat is not black. If P is false and Q is true, let's check statement 3: (~P or ~Q) becomes (true or false), which is TRUE. This means if Q is true, then statement 3 is also true. This contradicts the condition that *only one* statement is true. So, statement 2 cannot be the only true statement. Case 3: Assume statement 3 (~P or ~Q) is true. If (~P or ~Q) is true, then statement 1 (P) must be false. So, the cat is not black. And statement 2 (Q) must be false. So, the dog is not brown. Let's check for consistency: - Statement 1 (P) is false (consistent). - Statement 2 (Q) is false (consistent). - Statement 3 (~P or ~Q) is (True or True), which is True (consistent). This scenario satisfies the condition that only one statement (Statement 3) is true. Therefore, the cat is not black, and the dog is not brown.

Question 44

If A=1, B=2, C=3, and so on, what is the value of the word "EXAM"?

  • 36
  • 40
  • 43
  • 45
Explanation:

Assign numerical values to each letter based on its position in the alphabet: E = 5 X = 24 A = 1 M = 13 Summing these values: 5 + 24 + 1 + 13 = 43.

Question 45

Every time I have watered my plants on a Monday, they have grown significantly by the end of the week. Therefore, I conclude that watering plants on Mondays promotes their growth. This is an example of:

  • Deductive reasoning
  • Abductive reasoning
  • Inductive reasoning
  • Fallacious reasoning
Explanation:

Inductive reasoning involves forming a generalization based on specific observations or experiences. In this case, the speaker observes a recurring pattern (watering on Mondays followed by significant growth) and draws a general conclusion (watering on Mondays promotes growth). While the conclusion might not be scientifically proven without controlled experiments, the process of reasoning from specific instances to a general rule is inductive.

Question 46

A large cube is painted red on all six faces. It is then cut into 27 smaller identical cubes. How many of the smaller cubes have exactly two faces painted red?

  • 6
  • 8
  • 12
  • 16
Explanation:

When a large cube is cut into 27 smaller identical cubes, it means the large cube was divided into 3 sections along each dimension (3x3x3 = 27). Let 'n' be the number of divisions along one edge (here, n=3). - Cubes with 3 faces painted: These are the corner cubes. There are always 8 corners in a cube. - Cubes with 2 faces painted: These are the cubes along the edges, but not at the corners. Each edge has (n-2) such cubes. A cube has 12 edges. So, 12 * (3-2) = 12 * 1 = 12 cubes. - Cubes with 1 face painted: These are the cubes in the center of each face. Each face has (n-2)^2 such cubes. A cube has 6 faces. So, 6 * (3-2)^2 = 6 * 1^2 = 6 cubes. - Cubes with 0 faces painted: This is the innermost cube(s). There are (n-2)^3 such cubes. So, (3-2)^3 = 1^3 = 1 cube. Total cubes: 8 + 12 + 6 + 1 = 27. The question asks for cubes with exactly two faces painted red, which is 12.

Question 47

A sign reads: "The statement on the other side of this sign is false." If the statement on the other side reads: "The statement on the other side of this sign is true," what can be concluded about the truthfulness of these statements?

  • Both statements are true.
  • Both statements are false.
  • The statements are paradoxical; their truthfulness cannot be determined.
  • The first statement is true, and the second is false.
Explanation:

Let S1 be the statement on the front side: "The statement on the other side of this sign (S2) is false." Let S2 be the statement on the back side: "The statement on the other side of this sign (S1) is true." Assume S1 is true. If S1 is true, then S2 must be false (as S1 claims). If S2 is false, then its claim that S1 is true must be incorrect, meaning S1 is false. This leads to a contradiction: S1 is true and S1 is false. Assume S1 is false. If S1 is false, then its claim that S2 is false must be incorrect, meaning S2 is true. If S2 is true, then its claim that S1 is true must be correct, meaning S1 is true. This also leads to a contradiction: S1 is false and S1 is true. Since assuming either truth value for S1 (or S2) leads to a contradiction, both statements are paradoxical; their truthfulness cannot be determined.

Question 48

A company implements a mandatory "digital detox" policy, requiring employees to disconnect from work emails and messages after business hours. The HR department believes this will improve employee well-being and productivity. What is a core assumption behind this policy?

  • Employees are currently overworking due to digital connectivity.
  • Disconnecting from work will directly lead to improved well-being.
  • All employees have personal devices for work.
  • Employee productivity is currently low.
Explanation:

For a digital detox policy to improve well-being and productivity, the HR department must assume that the current level of digital connectivity outside of work hours is *detrimental* to these aspects. In other words, employees are currently overworking or experiencing burnout due to constant digital connection. If this weren't the case, the policy would have no problem to solve. Option (b) is a desired outcome, not the core assumption about the problem itself. (c) is a practical detail, not the underlying rationale. (d) is a potential consequence, not the fundamental assumption driving the intervention.

Question 49

2, 3, 5, 7, 11, ____. What is the next number in the sequence?

  • 12
  • 13
  • 14
  • 15
Explanation:

This sequence consists of prime numbers in ascending order. Prime numbers are natural numbers greater than 1 that have no positive divisors other than 1 and themselves. 2, 3, 5, 7, 11... The next prime number after 11 is 13.

Question 50

A car's engine suddenly stops working while driving. The driver notices that the fuel gauge is showing empty. Which of the following is the *most probable* explanation for the engine stopping?

  • A spark plug failed.
  • The car ran out of fuel.
  • The battery died.
  • The engine overheated.
Explanation:

While all the options could potentially cause an engine to stop, the additional information that 'the fuel gauge is showing empty' provides the most direct and probable cause. If there's no fuel, the engine cannot run. The other options are possible but are less probable given the explicit observation of an empty fuel tank.

Question 51

Which of the following does not logically follow from the statement: 'All birds can fly'?

  • If a creature cannot fly, then it is not a bird.
  • If a creature is a bird, then it can fly.
  • Some birds cannot fly.
  • Flying creatures must be birds.
Explanation:

The statement 'All birds can fly' means that the ability to fly is a characteristic of all members of the 'bird' category. It does not mean that only birds can fly, nor does it imply anything about non-flying creatures. 'If a creature cannot fly, then it is not a bird' is the contrapositive and is logically equivalent. 'If a creature is a bird, then it can fly' is the original statement. 'Some birds cannot fly' directly contradicts the original statement.

Question 52

A hospital administrator claims that the new electronic health record (EHR) system has reduced errors. Which of the following would be the strongest evidence to support this claim?

  • The time spent on documentation has decreased by 15%.
  • A survey shows that 80% of nurses feel less stressed.
  • The number of reported medication errors decreased by 20% after EHR implementation.
  • The hospital saved $50,000 in paper costs.
Explanation:

To strongly support the claim that the EHR system reduced errors, direct evidence of error reduction is needed. Comparing error rates before and after implementation, especially from a consistent and reliable source like incident reports, provides quantitative and relevant data. Option (a) is about efficiency, not error reduction. Option (b) is about staff perception, which is subjective. Option (d) is about cost savings, which is unrelated to error reduction.

Question 53

If a word is spelled forwards and backwards the same way, it is called a palindrome. Which of the following words is a palindrome?

  • RACE
  • MADAM
  • TABLE
  • APPLE
Explanation:

A palindrome reads the same forwards and backwards. Let's check the options: - LEVEL: L-E-V-E-L (forwards) and L-E-V-E-L (backwards). This is a palindrome. - RACE: R-A-C-E (forwards) and E-C-A-R (backwards). Not a palindrome. - STRESS: S-T-R-E-S-S (forwards) and S-S-E-R-T-S (backwards). Not a palindrome. - CIVIC: C-I-V-I-C (forwards) and C-I-V-I-C (backwards). This is also a palindrome. (Wait, let me ensure only one correct option. I will change options to ensure only one is correct.) Let's use a common example with distinct distractors.

Question 54

Which figure completes the sequence: Circle, Triangle, Square, Circle, Triangle, ____?

  • Pentagon
  • Square
  • Hexagon
  • Circle
Explanation:

The sequence follows a repeating pattern of three shapes: Circle, Triangle, Square. After 'Circle, Triangle', the next shape in the repeating pattern is Square.

Question 55

If 'WATER' is coded as 'XBUFS', how would 'FIRE' be coded using the same logic?

  • GJTE
  • GJSF
  • GHRE
  • HIRE
Explanation:

Let's analyze the coding for 'WATER' to 'XBUFS': W (+1 letter) X A (+1 letter) B T (+1 letter) U E (+1 letter) F R (+1 letter) S The pattern is to shift each letter one position forward in the alphabet. Applying this to 'FIRE': F (+1 letter) G I (+1 letter) J R (+1 letter) S E (+1 letter) F So, 'FIRE' would be coded as 'GJSF'.

Question 56

A student claims that getting a good night's sleep before an exam always leads to a better score. Which of the following statements *most directly challenges* this claim?

  • Sarah slept well before her exam and still failed.
  • Some students who cram all night also get good scores.
  • Studying consistently is more important than sleep.
  • Exam anxiety can negate the benefits of sleep.
Explanation:

The student's claim is 'If good sleep, then better score'. To directly challenge an 'always' statement, you need a counterexample. A situation where a student got good sleep but did not get a better score (or even got a worse score) would directly refute the 'always' aspect. Option (a) provides such a counterexample. (b) is a correlation, not a direct challenge to the 'always' aspect. (c) is about studying, not sleep. (d) is about stress, not directly challenging the sleep-score link.

Question 57

If 'CAT' is to 'TAC' as 'DOG' is to 'GOD', then 'BIRD' is to ____.

  • DRBI
  • BRDI
  • DRIB
  • RDBI
Explanation:

The pattern involves reversing the order of the letters in the word. CAT -> TAC (reversed) DOG -> GOD (reversed) Applying this to 'BIRD': BIRD -> DRIB (reversed)

Question 58

A marketing team proposes a new slogan for a product: "The best choice for discerning consumers." What is an implicit assumption made by this slogan?

  • Discerning consumers will immediately buy the product.
  • Discerning consumers prioritize quality above all else.
  • The product is the most expensive in its category.
  • All consumers are discerning to some degree.
Explanation:

The slogan targets 'discerning consumers' and claims the product is the 'best choice'. This implicitly assumes that discerning consumers actually exist as a targetable group and that they value 'the best choice' over other factors (like price, convenience, etc.). More specifically, it assumes that discerning consumers will recognize and agree that this product is indeed the 'best choice' for them. Option (a) is a desired outcome. Option (c) is too strong; it just needs to appeal to their discernment. Option (d) is about price, which isn't directly assumed by the slogan's wording.

Question 59

If 'A' is 20 miles north of 'B', and 'C' is 15 miles east of 'A', what is the shortest distance between 'B' and 'C'?

  • 25 miles
  • 30 miles
  • 35 miles
  • 40 miles
Explanation:

This forms a right-angled triangle. - From B, A is 20 miles North (let's call this the vertical side). - From A, C is 15 miles East (let's call this the horizontal side). The shortest distance between B and C is the hypotenuse of this right-angled triangle. Using the Pythagorean theorem: a^2 + b^2 = c^2 20^2 + 15^2 = c^2 400 + 225 = c^2 625 = c^2 c = sqrt(625) c = 25 miles.

Question 60

A doctor advises a patient to take a specific medication daily for a month. The doctor assumes the patient will follow the prescription. What kind of assumption is this?

  • A scientific assumption
  • A moral assumption
  • A behavioral assumption
  • A statistical assumption
Explanation:

This is an assumption about human behavior or compliance. The doctor is assuming that the patient will adhere to the instructions given. This is a pragmatic assumption necessary for the treatment plan to work, but it is not a guarantee.

Question 61

If 'SOUTH-EAST' becomes 'NORTH', what will 'NORTH-EAST' become?

  • NORTH-WEST
  • WEST
  • SOUTH
  • SOUTH-WEST
Explanation:

Let's visualize the compass points: N W E S 'SOUTH-EAST' is 45 degrees clockwise from South, or 135 degrees clockwise from North. If 'SOUTH-EAST' becomes 'NORTH', this represents a rotation. From SE to N, you rotate 135 degrees counter-clockwise (SE -> E -> NE -> N) or 225 degrees clockwise. Let's assume a 135-degree counter-clockwise rotation. 'NORTH-EAST' is 45 degrees clockwise from North. Applying a 135-degree counter-clockwise rotation to 'NORTH-EAST': NE (start) -> N (45 deg CCW) -> NW (90 deg CCW) -> W (135 deg CCW). So, 'NORTH-EAST' becomes 'WEST'. Let's verify with 225-degree clockwise rotation: SE (start) -> S -> SW -> W -> NW -> N (225 deg CW) NE (start) -> E -> SE -> S -> SW -> W (225 deg CW). Both rotations yield 'WEST'.

Question 62

All roses are flowers. Some flowers are fragrant. Therefore, some roses are fragrant. This conclusion is:

  • Valid, because roses are a type of flower.
  • Invalid, because the fragrant flowers might not be roses.
  • Valid, because all flowers are roses.
  • Invalid, because fragrance is subjective.
Explanation:

Let R = Roses, F = Flowers, G = Fragrant. 1. All R are F (R ⊆ F). 2. Some F are G (F ∩ G ≠ Ø). The conclusion 'Some roses are fragrant' (R ∩ G ≠ Ø) is not necessarily true. While it's possible, the premises do not guarantee it. The 'some flowers' that are fragrant might be flowers that are not roses. For example, if all roses are flowers, but only lilies (which are also flowers) are fragrant, then no roses would be fragrant. This is an example of an invalid syllogism.

Question 63

Which of the following is the best synonym for 'Ubiquitous'?

  • Rare
  • Limited
  • Omnipresent
  • Scarce
Explanation:

'Ubiquitous' means present, appearing, or found everywhere. 'Omnipresent' carries the same meaning.

Question 64

If you rearrange the letters 'CIFAIPC', you would have the name of a(n):

  • Country
  • City
  • Ocean
  • Animal
Explanation:

Rearranging the letters 'CIFAIPC' reveals the word 'PACIFIC'. The Pacific Ocean is an ocean.

Question 65

A town council is debating whether to build a new community center. Proponents argue it will increase community engagement. Opponents claim it will be too expensive. Which of the following, if true, would *most weaken* the proponents' argument?

  • The proposed budget for the center is double that of similar projects in other towns.
  • A recent survey indicates that most residents are not interested in community activities.
  • The town has not secured sufficient funding for the project.
  • There are already several underutilized public spaces in the town.
Explanation:

The proponents argue the center will increase community engagement. To weaken this, we need evidence that it won't achieve that goal. If a survey shows that residents are largely uninterested in participating in community activities, then building a center, regardless of its features, is unlikely to significantly boost engagement. Options (a) and (c) relate to cost/funding, which is the opponents' argument. Option (d) is about existing facilities, which doesn't directly address the willingness of residents to engage.

Question 66

What is the next number in the sequence: 100, 96, 90, 82, 72, ____?

  • 60
  • 62
  • 64
  • 66
Explanation:

Let's find the differences between consecutive numbers: 100 - 96 = 4 96 - 90 = 6 90 - 82 = 8 82 - 72 = 10 The differences are increasing by 2 each time (4, 6, 8, 10). The next difference should be 12. So, 72 - 12 = 60.

Question 67

Consider the statement: 'Every rose has its thorn.' Which of the following is a logically equivalent interpretation?

  • Only roses have thorns.
  • There is no rose without a thorn.
  • All thorny plants are roses.
  • Some roses exist without thorns.
Explanation:

The statement 'Every rose has its thorn' means that for any given rose, it possesses a thorn. This is an 'All A are B' type of statement. The logically equivalent interpretation is that there is no rose that does not have a thorn, or 'It is not true that some roses do not have thorns'. - Option (a) implies that only roses have thorns, which is not stated. - Option (b) is the direct translation. - Option (c) is a generalization that might be true in reality but not a logical equivalent of the specific statement. - Option (d) is an opposite conclusion.

Question 68

If 'PARIS' is to 'FRANCE' as 'ROME' is to 'ITALY', then 'TOKYO' is to ____.

  • CHINA
  • JAPAN
  • KOREA
  • THAILAND
Explanation:

The analogy establishes a relationship between a capital city and its country. Paris is the capital of France. Rome is the capital of Italy. Therefore, Tokyo is the capital of Japan.

Question 69

A doctor tells a patient, "If you take this medicine, you will feel better." The patient takes the medicine but does not feel better. What can be logically concluded?

  • The doctor's statement was false.
  • The patient did not take the medicine correctly.
  • The medicine is ineffective for everyone.
  • The patient's condition is untreatable.
Explanation:

This is a conditional statement: P → Q (If you take medicine, then you feel better). The patient took the medicine (P is true) but did not feel better (Q is false). When P is true and Q is false, the conditional statement P → Q is proven false. Therefore, the doctor's statement was false.

Question 70

Which of the following is the odd one out: CAR, BUS, TRAIN, BICYCLE?

  • CAR
  • BUS
  • TRAIN
  • BICYCLE
Explanation:

Car, Bus, and Train are all motorized vehicles typically used for transporting multiple people or heavy goods over longer distances. A Bicycle is a human-powered vehicle and typically carries one or two people for shorter distances. It's the only one that doesn't use an engine.

Question 71

If 'APPLE' is to '5' as 'BANANA' is to '6', then 'ORANGE' is to ____.

  • 5
  • 6
  • 7
  • 8
Explanation:

The pattern relates the word to the number of letters in the word. APPLE has 5 letters. BANANA has 6 letters. ORANGE has 6 letters.

Question 72

A politician states, "My opponent voted against the bill, therefore he does not care about the welfare of our citizens." This statement commits which logical fallacy?

  • Ad Hominem
  • Appeal to Emotion
  • Straw Man
  • Slippery Slope
Explanation:

This statement is an example of a 'Straw Man' fallacy. The politician distorts or misrepresents the opponent's position (voting against a bill) to make it seem like they don't care about citizens' welfare, which might not be the actual reason for the vote. The opponent might have voted against it for other reasons (e.g., specific clauses, cost, alternative solutions). It's an oversimplification and mischaracterization to attack a distorted version of the argument, rather than the actual argument.

Question 73

What is the next number in the sequence: 1, 8, 27, 64, 125, ____?

  • 180
  • 200
  • 216
  • 250
Explanation:

This is a sequence of perfect cubes: 1^3 = 1 2^3 = 8 3^3 = 27 4^3 = 64 5^3 = 125 The next number in the sequence would be 6^3 = 216.

Question 74

A company requires all employees to attend a mandatory diversity training. The HR department's primary goal is to foster a more inclusive workplace. What is the most critical assumption underlying this initiative?

  • The company currently has a non-inclusive workplace.
  • Diversity training is an effective method for promoting inclusivity.
  • All employees will willingly participate in the training.
  • The cost of the training is justifiable.
Explanation:

For mandatory diversity training to achieve the goal of fostering a more inclusive workplace, the most critical assumption is that such training effectively changes attitudes and behaviors. If the training is ineffective or even counterproductive, it won't achieve the primary goal. Option (a) is about current state, not the solution's effectiveness. Option (c) is about compliance, not the impact on inclusion. Option (d) is about cost, not the core assumption for success.

Question 75

If 'NORTH' is coded as 'SOUTH' and 'EAST' is coded as 'WEST', then 'NORTH-WEST' would be coded as ____.

  • SOUTH-WEST
  • SOUTH-EAST
  • NORTH-EAST
  • WEST-NORTH
Explanation:

The pattern involves changing each cardinal direction to its opposite: NORTH becomes SOUTH EAST becomes WEST Applying this to 'NORTH-WEST': NORTH becomes SOUTH WEST becomes EAST So, 'NORTH-WEST' would be coded as 'SOUTH-EAST'.

Question 76

All intelligent people are good at math. John is intelligent. Therefore, John is good at math. This is an example of:

  • Inductive reasoning
  • Abductive reasoning
  • Deductive reasoning
  • Analogical reasoning
Explanation:

This is a classic example of deductive reasoning. It starts with a general premise ('All intelligent people are good at math'), applies it to a specific case ('John is intelligent'), and draws a conclusion that must be true if the premises are true ('John is good at math').

Question 77

What is the next letter in the sequence: B, D, G, K, P, ____?

  • U
  • V
  • W
  • X
Explanation:

Let's find the number of letters skipped between consecutive terms: B (+2 letters) D D (+3 letters) G G (+4 letters) K K (+5 letters) P The pattern is to add an increasing number of letters (2, 3, 4, 5). The next step should be adding 6 letters to P. P (+6 letters: Q, R, S, T, U, V) leads to V.

Question 78

If 'BOOK' is to 'LIBRARY' as 'PAINTING' is to 'ART GALLERY', then 'ANIMAL' is to ____.

  • HOUSE
  • ZOO
  • FOREST
  • FARM
Explanation:

The analogy describes an item and the place where it is typically kept or displayed. Books are kept in a library. Paintings are displayed in an art gallery. Animals are typically kept or displayed in a zoo.

Question 79

A city council proposes a ban on single-use plastic bags, arguing it will significantly reduce plastic pollution. Which of the following, if true, would *most weaken* their argument?

  • The ban will disproportionately affect low-income residents.
  • Reusable bags require more energy to produce than plastic bags.
  • Most plastic pollution in the city originates from plastic bottles and packaging, not bags.
  • A public awareness campaign about recycling would be more effective.
Explanation:

The argument is that banning single-use plastic bags will reduce plastic pollution. To weaken this, we need evidence that the ban will not achieve this goal. If a significant portion of plastic pollution comes from sources other than single-use plastic bags (e.g., plastic bottles, industrial waste), then banning bags alone would have a limited impact on overall pollution. Options (a) and (b) describe unrelated issues. Option (d) suggests an alternative solution, but doesn't directly weaken the claim about the ban's effectiveness for pollution reduction.

Question 80

What is the next term in the sequence: Z1, Y2, X4, W8, V16, ____?

  • U32
  • T32
  • U24
  • T24
Explanation:

This sequence combines two patterns: 1. Letters: Z, Y, X, W, V. This is a reverse alphabetical order, decreasing by one letter each time. 2. Numbers: 1, 2, 4, 8, 16. This is a geometric progression where each number is multiplied by 2. Following the letter pattern, the next letter after V (going backward) is U. Following the number pattern, the next number after 16 (multiplying by 2) is 32. So, the next term is U32.

Question 81

If 'RAIN' is to 'WATER' as 'SNOW' is to 'ICE', then 'CLOUD' is to ____.

  • SKY
  • AIR
  • VAPOR
  • WIND
Explanation:

The analogy relates a form of precipitation to its primary component. Rain is composed of water. Snow is composed of ice (frozen water). Clouds are composed of water vapor (or tiny water/ice droplets).

Question 82

A company is considering investing in a new technology. The CEO states, "We must adopt this technology, otherwise we will fall behind our competitors and eventually go out of business." This statement is an example of which logical fallacy?

  • Ad Hominem
  • False Dilemma
  • Slippery Slope
  • Appeal to Authority
Explanation:

The CEO's statement presents a chain of increasingly negative consequences, claiming that adopting the technology is the only way to avoid a catastrophic outcome (going out of business). This is a 'Slippery Slope' fallacy, where a relatively minor first step is presented as inevitably leading to a series of significant and undesirable consequences, without sufficient evidence for each step.

Question 83

What is the missing number: 7, 14, 21, ___, 35, 42?

  • 24
  • 26
  • 28
  • 30
Explanation:

This is a simple arithmetic progression where each number is a multiple of 7. The sequence is 7 × 1, 7 × 2, 7 × 3, ..., 7 × 6. 7 × 1 = 7 7 × 2 = 14 7 × 3 = 21 The missing number is 7 × 4 = 28. 7 × 5 = 35 7 × 6 = 42

Question 84

If 'FOREST' is to 'TREE' as 'OCEAN' is to 'FISH', then 'CITY' is to ____.

  • PEOPLE
  • BUILDING
  • STREET
  • CAR
Explanation:

The analogy describes a large entity and a typical, common component or inhabitant within it. A forest is characterized by trees. An ocean is characterized by fish. A city is characterized by buildings.

Question 85

A researcher states, "The new vaccine significantly reduces the risk of infection." Which of the following is an unstated assumption in this claim?

  • The vaccine has no side effects.
  • There is a measurable risk of infection without the vaccine.
  • The vaccine provides complete immunity.
  • The vaccine is affordable for everyone.
Explanation:

For the vaccine to 'significantly reduce' the risk, the researcher implicitly assumes there's a baseline risk of infection *without* the vaccine that the vaccine is being compared against. If there's no risk to begin with, the vaccine can't reduce it. Option (a) is a desired outcome, not an assumption. Option (c) is too strong; it might not be 100% effective. Option (d) is about side effects, not the primary claim of risk reduction.