Logical ReasoningDifficulty: Easy

PT21 S2 Q13 Explanation

Astronomers have long thought that

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

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Full official LSAT questions are available through LawHub. This page provides LSAT Lab's explanation, strategy, and review tools without republishing the full official question.

Stimulus

Astronomers have long thought that the irregularity in the orbit of the planet Neptune was adequately explained by the gravitational pull exerted on Neptune by the planet Pluto. The most recent observations of Pluto, however, indicate that this planet is much too pull on Neptune that astronomers once thought it did.

What this question is testing

Most Supported

Your task

Break the argument into its conclusion and evidence, then do exactly what the question stem asks with that structure.

Common trap

Answers that sound relevant to the topic but don't connect to the argument's actual reasoning.

Winning move

Predict what a right answer must do, then test each choice against the conclusion-evidence gap.

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

The question
13.

If the statements above are true, they provide the most support for which one

Answer choices

  1. Trap4% picked this

    Neptune is somewhat larger than scientists once believed it

  2. Trap3% picked this

    The orbit on Neptune is considerably more irregular than scientists once

  3. Trap3% picked this

    There exists another, as yet undiscovered planet with an orbit beyond

  4. Correct89% picked this

    The gravitational pull of Pluto is not the sole cause of

    Why this is right

    Answer D is correct.

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

  5. Trap1% picked this

    Further observations of Pluto will eventually show it to be even smaller than it is

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