Logical reasoning PrepTest 106 · Section 3 · Question 22

Question prompt

Researcher: The role of Remaining source text redacted.
Why the credited answer is right

Credited answer: B

The notes below walk through why it fits the stem and how to eliminate the rest.

Argument or Facts

Argument

Valid or Flawed

Flawed

Question Type

Strengthen with Necessary Premise Questions

Stimulus Summary

Humans choose their sexual behavior, so pheromones don’t play a role.

Answer Anticipation

This question ends up being mostly about cutting out the irrelevant information, as once you get the argument down to it’s premise/conclusion, it’s relatively straightforward.
To get down to just the core, we should start with the conclusion. That “So” at the end tells us that the final sentence is the main point - pheromones are a vestige of our evolutionary past. Why does the Researcher believe that’s the case? Because pheromones serve a function in sexual behavior, but humans choose how they behave.
All of that other information? It’s there to distract you! The conclusion is about humans, so the information about animals and about history is all out of scope.
Focused on the conclusion, does the fact that humans exercise choice in their sexual behavior a sign that pheromones don’t play a role? There’s no premise establishing that. Pheromones could play some role - for example, they could create a “spark” that a person then can decide whether to act on. The argument is assuming that chemicals/pheromones can’t play a role in a voluntary action, so let’s find an answer stating that.

Answer choices

  1. A
    whatever does not have Remaining source text redacted.
    Why choice A is not credited
    The argument concludes that something doesn’t have a chemical explanation, so there’s nothing established as not having such an explanation, making this answer out of scope.
  2. B
    voluntary action cannot have Remaining source text redacted.
    Why choice B matches the stem
    This answer connects the premise and conclusion. The argument concludes that human sexual behavior isn’t explained by chemicals/pheromones because it involves voluntary action, assuming that voluntary actions can’t have chemical explanations. If they can, then pheromones may still play a role in sexual behavior, invalidating the argument. This answer is thus a necessary premise for the argument.
  3. C
    free will can be Remaining source text redacted.
    Why choice C is not credited
    The argument relies on animal sexual behavior being involuntary, but that doesn’t mean they can have free will in other areas of their lives.
  4. D
    voluntary action cannot have Remaining source text redacted.
    Why choice D is not credited
    The conclusion is that human behavior doesn’t have a chemical explanation, not that it doesn’t have an evolutionary explanation. While the conclusion does mention evolution, it establishes pheromones as a piece of evolutionary history - it doesn’t rule out an evolutionary explanation for free will.
  5. E
    there is a psychological Remaining source text redacted.
    Why choice E is not credited
    If anything, this answer weakens the argument by tying pheromones into psychology/free will.

What this tests

Question analytics

Based on historical answer selection rates for this question.

Answer choice distribution

  1. A 13%
  2. B Credited 65%
  3. C 9%
  4. D 8%
  5. E 5%

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