According to a recent Stanford study, how well unsaturated vegetable

Okay, I could see lots of open questions here.

Now, let me chime in.

As you all know whenever a clause is used in the subject of the independent clause, it is considered singular. So, here our clause is "how well unsaturated vegetable oils ....". Hence, we need singular verb "depends", thus A, B and C are out.

Now, let's discuss about option D and E.

This question is the perfect example where meaning is very important to understand.

The meaning of the sentence is how well these oils hold up depends on the some of the foods consumed when you are taking very less quantity of fats.

Now, if I talk about option D, it is implying the meaning "how well these oils hold up depends on food eaten when you are consuming very less fats.".

Did you all see the change in the meaning? In the 1st option, I am talking about specific types of food while in the 2nd I am talking about only food. It could be anything. Thus, I am changing my meaning in option D. This is not allowed.

Now, let's come to the confusion of whether fats are countable or uncountable. So, my friends there has been long discussion on this in the past on different forums and it has been taken as "Fat can either be an adjective (in that case is always singular) or a noun (thus it can be plural)."

An easier example to understand would be that chicken fat and pig fat are fats from two different animals.

Thus, I would not reject any answer choice based on countable vs uncountable nature of fat. It may also mean I am talking about 2-3 different sources of fats and thus saying fewer saturated fats.

Key Note: Meaning is by far very important while selecting any answer choice.

Finally, my friends megakee9 Adityasekar : Doesn't make sense or seems better is NEVER a reason to select or reject any answer choice on GMAT.

Does that make sense?