Cant it be A?
If you need to be skilled at auto mechanics you should be a safe driver?
I guess when picking A, you may think the argument as the cause-effect argument in which: be taught auto mechanics --> drive safely.
I think it is not like the case: top schools --> become outstanding students which can be weaken by saying students who have been outstanding --> top schools.
Instead of thinking that the argument is a kind of the cause-effect, we see the argument clearly absurb and irrelevant. (C) clearly says that "be taught auto mechanics" and "drive safely" are not related at all.
You can see the same reasoning with the question below from GMAT real test paper (officially published):cr-teenagers-are-often-priced-out-of-the-labor-market-89217.html
hope it helps.
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