 Know that you have to answer the question before you continue on to the next question and that applies to the entire NCLEX exam. So you cannot skip a question and then come back later because the case study question number three might actually help you answer question number two and you will not be able to proceed unless you make a choice. So you can't skip it, you can't leave it blank. You have to make a selection and then the next question will come up. So if you don't for sure know the answer just do your best, take your best guess and move on rather than fretting and losing some valuable time.