Logical reasoning PrepTest 112 · Section 1 · Question 13

Question prompt

When astronomers observed the Remaining source text redacted.
Why the credited answer is right

Credited answer: C

The notes below walk through why it fits the stem and how to eliminate the rest.

Argument or Facts

Facts

Valid or Flawed

NA

Question Type

Paradox Questions

Stimulus Summary

September 1995 - Scientists see a comet get bright because of emissions of gas and dust and correctly say it’s breaking up; they keep telescopes trained on it
November 1995 - Scientists see the comet breaking up for the first time

Answer Anticipation

This argument lays out a timeline for a comet breaking up, and timelines are important on the LSAT. We should focus on that timeline as we clearly state the paradox we’re being tasked with resolving.
So what’s the weird situation here? Well, the scientists first (correctly) called that a comet was breaking up in September. However, despite careful monitoring, they didn’t see it breaking up until November.
So how could the first signs of breaking up happen two months before the scientists could actually see it breaking up? That’s what we need to resolve. Anything that explains this timeline - how it could take 2 months from the first signs for the actual breaking up to be witnessed - will serve as an explanation here.

Answer choices

  1. A
    Comets often do not Remaining source text redacted.
    Why choice A is not credited
    The argument ties the gas and dust to brightness, which was witnessed in September, so this answer gets the timeline wrong.
  2. B
    The reason comets become Remaining source text redacted.
    Why choice B is not credited
    This answer might explain the one phenomenon, but not why it took two months for the scientists to see the comet breaking up after that process had apparently started in September.
  3. C
    Gas and dust can Remaining source text redacted.
    Why choice C matches the stem
    This answer explains that a comet breaking up is a process, and the gas/dust emission can happen early on in that process. If that’s the case, then the timeline from the stimulus makes sense, with the brightness from those emissions happening weeks/months before the comet was seen actually fracturing.
  4. D
    The amount of gas Remaining source text redacted.
    Why choice D is not credited
    There’s no indication that the comet here grew brighter between September and November, so this answer doesn’t deal with the information we have.
  5. E
    The comet passed close Remaining source text redacted.
    Why choice E is not credited
    What caused the comet to break up isn’t the question - it’s why scientists witnessed the gas/dust emissions that are associated with it breaking up months before the breakup itself that needs explaining.

What this tests

Question analytics

Based on historical answer selection rates for this question.

Answer choice distribution

  1. A 16%
  2. B 3%
  3. C Credited 74%
  4. D 6%
  5. E 1%

Deeper help

Ask follow-ups on any step

Optional AI tutor mode will let you interrogate assumptions, compare answers, and drill weak patterns without leaving the page.

Human-written explanations stay primary; AI is an add-on when you want it.

Discussion

View all discussions Start a discussion