A recent study found that people who drink at least two cups of coffe

Question

A recent study found that people who drink at least two cups of coffee per day are 30% less likely to develop Parkinson's disease. The study's authors concluded that the caffeine in coffee must be responsible for this protective effect.

Which of the following, if true, would most weaken the conclusion that caffeine is responsible for the protective effect?

A) People who drink coffee regularly tend to have higher levels of physical activity than those who do not.
B) The study only surveyed people who were already diagnosed with Parkinson's disease.
C) Caffeine has been shown to have neuroprotective effects in laboratory experiments.
D) The study controlled for other factors that might influence the development of Parkinson's disease.
E) The study's authors have received funding from a major coffee company.

leyermo1234 · Answer

Answer: A)  People who drink coffee regularly tend to have higher levels of physical activity than those who do not.

Explanation:  The question asks us to find the answer choice that would most weaken the conclusion that caffeine is responsible for the protective effect. Answer choice A suggests that people who drink coffee regularly tend to have higher levels of physical activity than those who do not. This could be an alternative explanation for the reduced risk of Parkinson's disease, rather than the caffeine itself. Perhaps it is the physical activity, rather than the caffeine, that is responsible for the protective effect. This would weaken the conclusion that caffeine is responsible for the protective effect.

AnuK2222 · Answer

What is the basis on which we are eliminating option E?

Feb2024 · Answer

KarishmaB   MartyMurray   Bunuel   GMATNinja

Can you provide reasoning to eliminate options B & E? I understand these weaken the argument more to a more degree that Option A.

Thanks in Advance!

Posted from my mobile device

MartyMurray · Answer

Here's (B).

B) The study only surveyed people who were already diagnosed with Parkinson's disease.

That choice is pretty ridiculous since it doesn't make sense that the study could find that people who drink at least two cups of coffee per day are 30% less likely to develop Parkinson's disease without considering people who have not developed the health issue.

So, I guess in a way it weakens the case for the conclusion, but really the issue is that the choice doesn't make sense.

Here's (E).

E) The study's authors have received funding from a major coffee company.

I guess we can choose (A) over this one since (A) clearly wrecks the case for the conclusion whereas this choice doesn't clearly indicate that the study is flawed. It only casts a little suspicion on it.

Overall, I don't think this question accurately represents how a GMAT CR question works.

A recent study found that people who drink at least two cups of coffe

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A recent study found that people who drink at least two cups of coffe