Logical ReasoningDifficulty: Medium

PT105 S4 Q20 Explanation

James: Chemists have recently invented

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

TopicsMethod

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Stimulus

James: Chemists have recently invented a new technique for extracting rhodium, an element necessary for manufacturing catalytic converters for automobiles, from nuclear waste. Catalytic converters function to remove noxious gases from automobile exhaust. The use of nuclear one way to creating a cleaner environment.

Marta: The technique you mention, though effective, is still at an experimental stage, so there has been no shift in the sources of in manufacturing catalytic converters.

What this question is testing

Method

Your task

Describe how the argument proceeds — the technique it uses to reach its conclusion.

Common trap

Answers that describe a method the argument doesn't actually use.

Winning move

Track the role each statement plays, then match that to the choice describing the same moves.

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

The question
20.

Marta responds to James's argument

Answer choices

  1. Trap8% picked this

    casting doubt on the accuracy of the claims made by James in support

  2. Trap0% picked this

    questioning the credibility of advocates of

  3. Trap9% picked this

    indicating that James is assuming the truth of the conclusion that he

  4. Correct79% picked this

    pointing out a fact that James, in drawing his conclusion, did not

    Why this is right

    Answer D is correct.

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

  5. Trap4% picked this

    point out that James's premises are no more plausible than is

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