Remember that nursing exams are notorious for being clever and slick..um, I mean needing critical thinking skills. The questions in your book are there as a learning tool. Exams are there to test your knowledge with curve balls and rationals that might make you say "oh, gimme a freakin' break..yeah right." Take the test as if the people who wrote it was trying to be witty and clever.
For example, I had a test question on a med called Nipride (an extremely potent antihypertensive drip). One change in the rate can make the bp drop. The question asked about systemic vascular resistance. Nipride does lower it b/c it a potent vasodilator. But the story said the pt has a BP of 89/39 with a high vascular resistance and the answer was nipride. Complete bs. But the question wanted to know what drug lowered SVR and increase cardiac output, thus theoretically raising the blood pressure. I the real world, there would be some fluid involved with the gtt, but that's not how exams work. I got the question right because I knew the the bp was there as a curve ball. If the bp was 110/50, the answer would be obvious, but NO...they can't do that! They got to clever and put in some shady rational because theoretically, blah, blah, blah. Sometimes, it's laughable. You don't hang nipride on hypotensive pts. I know, I know the SVR..just whatever.
So next time you take your exams, look at the questions from different angles. Know that they are being clever. If something doesn't make sense, think outside the box. That's what they want you to do anyway. So, the point is, they want you to think outside the box, even if the answer is a complete joke. It's why you should never read into the question. That will pull your scores back up. By the time you take the NCLEX, you should be able to say "I know what answer this question wants...it's complete bs, but whatever. I know what they are getting at." That's when you know you'll do well.