LSAT 70, Reading Comprehension, Q6

DISCUSSION: A pathogen is something that causes diseases and replicates itself (lines 2-5). Prions appear to be pathogens (see lines 19-24).

We used to think that pathogens had DNA, but prions lack DNA (see line 22).

This question asks us to assume that all the facts we learned about prions are true. Remember, we’re looking for things that must be false. It’s possible that certain answers could be false, but that’s not enough. B and C aren’t necessarily true, for instance, but they could be true, and that’s all you need.

___________

1. CORRECT. The contrapositive of this answer is: pathogens have nucleic acid. But the theory says that prions are pathogens and that they lack nucleic acid (line 22). So this answer contradicts the passage.
2. This seems true. The passage implies that the discovery of prions was recent.
3. Lines 1-3 support this. Pathogens are things that cause disease.
4. If the prion theory is correct, then prions are pathogens, and prions cause CJD. So this answer would be true.
5. This seems true. If the prion theory is correct, then prions are also pathogens. Prions are not bacteria, viruses, fungi or parasites.

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