Columnist: People should avoid using a certain artificial fat that has been touted as a resource for those whose medical advisers have advised them to reduce their fat intake. Although the artificial fat, which can be used in place of fat in food preparation, has none of the negative health effects of fat, it does have a serious drawback: it absorbs certain essential vitamins, thereby preventing them from being used by the body.

In evaluating the columnist's position, it would be most useful to determine which of the following?

(A) Whether increasing one's intake of the vitamins can compensate for the effects of the artificial fat
(B) Whether the vitamins that the artificial fat absorbs are present in foods that contain the fat
(C) Whether having an extremely low fat intake for an extended period can endanger the health
(D) Whether there are any foods that cannot be prepared using the artificial fat as a substitute for other fats
(E) Whether people are generally able to detect differences in taste between foods prepared using the artificial fat and foods that are similar except for the use of other fats
OA is A.
Thanks for your explaination

you need to boil the columnist's position down to its essence, which is basically this:
fat absorbs vitamins that are essential.
therefore, body doesn't get vitamins.
therefore, bad news.

the second 'therefore' here is unassailable (it's definitely bad news if your body doesn't get vitamins), so the only thing that might sway the argument in one direction or the other is the first 'therefore'. if we could break the connection between absorption of vitamins and robbing the body of vitamins, then we could possibly destroy the argument.

choice a breaks the connection, because it introduces the possibility that the body might get the vitamins anyway, despite the absorption of some of those vitamins by the fat.

b is irrelevant, as it doesn't matter where the vitamins come from (only whether they're properly absorbed)

c is irrelevant, as the possible dangers of low-fat diets don't affect the above line of reasoning (the dangers of the artificial fat) at all

d is irrelevant: which foods can contain the artificial fat has nothing to do with whether it will rob the body of vitamins

e is irrelevant: taste has no bearing on the discussion at hand

hope that helps.