Logical reasoning PrepTest 134 · Section 3 · Question 26

Incorrect. This answer is a reversal of sorts. We need an answer that the expectations and actions to justify the conclusion that it's rational, not a premise about rational consumers.

Incorrect. Establishing that certain behavior is irrational doesn't help to justify a conclusion that behavior is rational.

Incorrect. The conditional established in the stimulus is about what a consumer "expects," not what is actually true, so this answer is out of scope. Just because something is true doesn't mean that it'll match expectations!

Incorrect. This answer starts with rational consumers instead of allowing a conclusion to be drawn that consumers acting in a certain way are rational, so it doesn't help to justify the conclusion.

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Strengthen with Sufficient Premise

Stimulus Summary:
Getting full info on product purchases is hard and costly.
Expectation is that benefits of getting full info won't outweigh costs → Rational to not get full info
Therefore - Consumers are rational to not get full info

Answer Anticipation:
As with many Strengthen with Sufficient Premise questions, the stimulus here relies on conditional logic ("unless"). When that happens, the argument generally either tries to chain together several conditionals, or it tries to apply the conditional to a specific situation. As there's only one conditional here, this is an example of the latter.

When that happens, the argument generally fails to establish that the sufficient condition is met in the situation the conditional is being applied to. Here, that condition is that a shopper doesn't expect spending the time to research all products to be worth it. However, the stimulus establishes only that doing the research is costly and expensive. In order to ensure that the sufficient condition is met, then, it must be established that the benefits of doing the research don't justify that time and expense. Let's find the answer choice stating that!

Answer Explanation:
This answer directly establishes that the consumers in question don't believe that the benefits of researching a purchase will outweigh the cost. That ensures the conditional applies in the situation described and the conclusion can be properly drawn.

Key Takeaway:
Strengthen with Sufficient Condition questions frequently feature conditional logic. When there's a single conditional statement and the argument attempts to apply it to a specific situation, it's likely that the argument will fail to actually establish that the sufficient condition is met, and the correct answer will do so.