I think the answer to the OP's question, especially in med school, lies in one's ability to answer secondary and tertiary level questions as opposed to straight up recall of facts. These types of questions require an ability to make connections that go beyond simply how much does someone know.
For example, you might know the mechanism of CF and that it causes decreased absorption of fat soluble vitamins, the fat soluble vitamins are A,D,E,K, and decreased vit. D leads to rickets, etc. You would get all those questions right if they were asked individually. However, most med school exams and definitely Step 1 will give you a scenario of a kid with some symptoms of CF including say mucosal bleeding (vit k deficiency) and ask what the etiology of his bleeding is. You now have to recognize that the kid in the vignette has CF, understand how there is decreased fat soluble vitamin absorption, know that vit. K is one of those vitamins and that vit. K deficiency leads to bleeding problems in order to get the question right.
You may recognize right off the bat that this is CF, but if you can't make those next logical leaps then you will be wondering WTF does bleeding have to do with CF?
Just a thought...