What is the secret!!!

When taking the nursing exams I am stumped. I study all my reading materials and when it comes to talking the test I feel blindsided and do not know which answer to pick! I know two are most definitely wrong and the other two need to be semi right but here is ONLY one correct answer. Is there any secret to knowing right off the bat the two that are not the answer. Are there any key words etc that I should be aware of so I know what ones to eliminate !!!! Thank you