I don't understand the correct answer at all. I don't see how it could possibly be correct. I chose C which looked like the absolute only correct option.
Focus on the conclusion of the stimuli and a question stem that attacks it.
Conclusion: the author hypothesized that smoking by itself can induce snoring.
Well, the correct answer must weaken this statement, ie, smoking does NOT by itself induce snoring. That is exactly what answer choice A does - it is not smoking itself that induce snoring but another contributing factor.
garryathwal is correct. Answer choice "C' is wrong because if "most snorers do not smoke", it does not refute the possibility that it may be the case that smoking by itself CAN induce the snoring for "some snorers".
Comments
Focus on the conclusion of the stimuli and a question stem that attacks it.
Conclusion: the author hypothesized that smoking by itself can induce snoring.
Well, the correct answer must weaken this statement, ie, smoking does NOT by itself induce snoring. That is exactly what answer choice A does - it is not smoking itself that induce snoring but another contributing factor.
garryathwal is correct. Answer choice "C' is wrong because if "most snorers do not smoke", it does not refute the possibility that it may be the case that smoking by itself CAN induce the snoring for "some snorers".