LSAT 143 | Section 4 | Logical Reasoning: Q8

LR Question 8 Explanation

QUESTION TEXT: The giant Chicxulub crater in Mexico provides…

QUESTION TYPE: Weaken

CONCLUSION: The asteroid strike at Chicxulub in Mexico probably didn’t cause the extinction of the dinosaurs.

REASONING: There is not much evidence an asteroid strike could affect the whole world. Larger craters occurred without extinctions.

ANALYSIS: This seems like a bulletproof argument. I couldn’t prephrase anything. The argument has clearly eliminated the possibility that the asteroid strike caused extinction globally.

When you can’t prephrase, just load the facts into your short term memory and keep an open mind. The right answer raises a possibility I didn’t consider: most dinosaurs lived near where the asteroid struck.

___________

1. This strengthens the argument. It shows most dinosaur extinctions were not caused by the asteroid.
2. This just tells us a fact about the crater. But it doesn’t tell us whether the Chicxulub strike could have been severe enough to cause extinction.
3. This sounds tempting, but the stimulus already said the asteroid could kill dinosaurs – locally. This answer doesn’t say the asteroid killed any dinosaurs in other areas.
4. This doesn’t matter. The argument only mentioned other asteroids to show that craters could occur without causing extinction.
5. CORRECT. The argument tells us the asteroid could have killed dinosaurs in the area around the crater. This answer tells us that most dinosaurs did live around the crater – so they might have died.