Logical ReasoningDifficulty: Hard

PT136 S4 Q17 Explanation

Although Pluto has an atmosphere

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

TopicsSufficient Assumption

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Stimulus

Although Pluto has an atmosphere and is much larger than any asteroid, Pluto is not a true planet. Pluto formed in orbit around the planet Neptune and was then ejected from orbit moon, was captured by Neptune's gravity.

What this question is testing

Sufficient Assumption

Your task

Find the assumption that, if added, guarantees the conclusion follows.

Common trap

Answers that only partly bridge the gap, leaving the conclusion unproven.

Winning move

Identify the new term in the conclusion and pick the choice that links it to the evidence.

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

The question
17.

The conclusion of the argument follows logically if which one of the

Answer choices

  1. Too Weak7% picked this

    No celestial body can simultaneously be a moon and

    The problem with M ? TP this answer is that Pluto is not a moon since it no longer orbits Neptune.

  2. Too Weak13% picked this

    Not all celestial bodies that have an atmosphere and orbit the sun

    This supports the A + OS ?some? ~TP view that Pluto is not a true planet but is too weak to ensure it.

  3. Wrong Trigger8% picked this

    If Pluto had not been ejected from its orbit around Neptune, Pluto would not have its current orbit around the sun and

    Pluto was ejected from its orbit around Neptune, so this answer does not apply.

  4. Too Weak5% picked this

    The size of a celestial body in orbit around the sun is not relevant to determining whether or not

    While this would preclude the opposing point from proving that Pluto is a true planet it is not strong enough to prove that Pluto is not a planet.

  5. Correct67% picked this

    For a celestial body to be a true planet it must have formed in orbit

    Why this is right

    This bridges the TP ? ~FAP gap between forming within the orbit around a planet and not being a true planet.

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

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