Question Type:
Strengthen (the claim, not the argument, in case that matters)
Stimulus Breakdown:
Conclusion: Asteroids strike Earth through an organized natural process.
Evidence: A halo-like swath across the N. Hemisphere that appeared at the end of the Cretaceous period.
Answer Anticipation:
I guess she's assuming that "halo-like swath of impact craters" somehow indicates "highly organized natural process".
Correct Answer:
D
Answer Choice Analysis:
(A) We don't care what caused mass extinctions; we're only evaluating whether asteroids strike randomly or whether there's a natural process that governs it.
(B) This has nothing to do with whether impacts are random or organized.
(C) Maybe. Is 'single cluster' indicative or ORGANIZED, not RANDOM? Is it indicative of "a highly organized natural process"? Not really. A single cluster of meteors could easily have broken off an asteroid by some random impact with another asteroid.
(D) Yes! This sounds like asteroid impacts ARE governed by some natural process (sucked by gravity into specific orbits before impact).
(E) If anything, this would weaken the use of the halo-swath as evidence of an organized, natural process. Something that happened only once sounds more RANDOM than ORGANIZED.
Takeaway/Pattern: Ahhh, so it DID matter that the question stem said 'claim', not 'argument/reasoning'. The geophysicist DID present evidence for her claim, i.e. she DID present an argument, but the correct answer is only related to the conclusion, the geophysist's claim. The halo-swath piece of evidence just gave LSAT some fodder for making trap answers.
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