Logical ReasoningDifficulty: Medium

PT133 S2 Q1 Explanation

Studies have shown

A free, expert breakdown of this official LSAT Logical Reasoning question.

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Stimulus

Studies have shown that treating certain illnesses with treatment X produces the same beneficial changes in patients' conditions as treating the same illnesses with treatment Y. Furthermore, treatment X is quicker and less expensive than treatment treatment X should be preferred to treatment Y.

What this question is testing

Weaken

Your task

Find the choice that makes the argument's conclusion less likely to be true.

Common trap

Answers that look negative but attack a claim the argument never relied on.

Winning move

Find the assumption the argument depends on, then pick the choice that undermines it.

Reading along? Open the full official question in LawHub — we show a fragment here and keep the reasoning in our own words.

The question
1.

Which one of the following, if true, would most weaken the

Answer choices

  1. Correct81% picked this

    Unlike treatment Y, treatment X has produced harmful side effects in

    Why this is right

    Harmful side effects would be considered a disadvantage by anyone.

    Skill tested: Weaken · how this choice captures the argument's function is the move to repeat next time.

  2. Out Of Scope6% picked this

    There are other illnesses for which treatment Y is more effective

    Treatment Y’s ability to treat other illnesses are not relevant to the argument’s conclusion about the illnesses discussed in the argument.

  3. Out Of Scope2% picked this

    Until recently, treatment X was more expensive than

    The argument is about which treatment should be preferred today. Whether treatment X was more expensive in the past is not relevant.

  4. Out Of Scope3% picked this

    Treatment Y is prescribed more often by physicians than

    The argument is about what should be the case, not what is the case. So whether doctors prescribe treatment Y more than treatment X doesn’t matter in determining which treatment they should recommend.

  5. Out Of Scope9% picked this

    A third treatment, treatment Z, is even quicker and less expensive

    Treatment Z is not relevant in determining whether treatment X should be preferred to treatment Y or vice versa.

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