Critical Reasoning

Researchers have noticed that people whose blood shows abnormally low levels of calcium usually have laryngeal polyps, which can permanently damage vocal cords and result in partial or even total loss of voice. In order to reduce the risk of polyps, the researchers recommend a diet high in calcium-rich foods such as dairy and green, leafy vegetables.

Which of the following, if true, most strongly suggests that following the researchers' recommendation would NOT be effective?

A)Dairy contains compounds that are difficult for many people to digest.
B)Laryngeal polyps sometimes disappear without treatment.
C)Laryngeal polyps cause a change in body chemistry that blocks the absorption of calcium.
D)Fresh vegetables are not always available in all seasons
E)Low levels of calcium can sometimes be remedied with vitamin pills.

Can you guys pls explain this.

This is a very standard cause and effect set up. Be ready to see something like this on test day!

So the question shows us the CORRELATION between two things: laryngeal polyps and low levels of calcium.

Then they arbitrarily decide that one of the two caused the other. So in this case they say that the low calcium levels caused the polyps.

Yet they never seem to consider that the cause could flow the other way. The polyps could somehow cause the lower calcium levels. This is what choice C points out.

Another example of this is a question that said that people with a laptop computer earn more money than people who do not own a laptop. Then the argument concluded, "buy a laptop and you will earn more money."

Yet clearly it makes more sense that people who earn more money can afford a laptop so the correct answer had the cause reversed more money causes laptop ownership.

Then you can have a "third cause." Take for example violence and ice cream consumption. Levels of Violence and of ice cream consumption are almost perfectly correlated in many regions of the U.S. So the question becomes does ice cream consumption cause violence or the other way around?

Of course it is neither. The truth is that a third cause, higher temperatures, leads both to more ice cream eaten and to higher levels of violence.

So watch for the third cause as well.

This is indeed a causation passage, where the author says that X causes Y. In this case, calcium deficiency causes laryngeal polyps. The problem with this sort of argument is that it may be the other way around. What I mean is, it could be that laryngeal polyps cause a calcium deficiency.

However, what we're asked to do with this question is to find an answer choice that most strongly REFUTES the researchers' recommendation. The recommendation is to eat a diet high in calcium (because of the X causes Y argument noted above). So we're looking for something that refutes the idea that eating a diet high in calcium will prevent laryngeal polyps.

A - This answer doesn't "most strongly" refute the recommendation. Even if true, the recommendation is not strictly limited to dairy food. Eliminate it.

B - This answer is irrelevant to any argument about diet. Eliminate it.

C - This answer does refute the recommendation! If laryngeal polyps block the absorption of calcium, then there is no point to eating a diet high in calcium to get rid of polyps - the action of the polyps themselves will prevent the diet from having any effect.

D - Like A, this answer does not "most strongly" refute the recommendation. Fresh vegetables are not the only recommended food item in this diet. Eliminate it.

E - Like B, this answer is irrelevant to any argument about diet. Eliminate it.

The correct answer is C.

My answer is also "C"

I agree that if laryngeal polyps causes a calcium deficiency then there's no need a diet high in calcium-rich foods such as dairy and green, leafy vegetables.