Critical Reasoning

Studies have shown that specialty sports foods contain exactly the same nutrients in the same quantities as do common foods from the grocery store. Moreover, sports foods cost from two to three times more than regular foods. So very few athletes would buy sports foods were it not for expensive advertising campaigns.

Which one of the following, if true, most weakens the argument?

(A) Sports foods are occasionally used by world-famous athletes.
(B) Many grocery stores carry sports foods alongside traditional inventories.
(C) Sports foods are easier than regular foods to carry and consume during training and competition.
(D) Regular foods contain vitamins and minerals that are essential to developing strength and endurance.
(E) Sports foods can nutritionally substitute for regular meals.

OA is C
Does the OA truly weaken this statement? I would love to be better lectured on this by an expert. Thanks
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