Most exams cover material you’ve studied but sometimes the PMP exam includes questions that were not in the version of the PMBOK guide that you have studied. This can really throw you for a loop but if you’re prepared for it, it won’t be such a shock. The thing to remember is that the PMBOK guide is just that - a guide, not an exact accounting of every tool and concept that you will be using as a project manager and PMP. For instance, techniques such as AON and AOA are still used by project managers around the world even though they were removed from the PMBOK Guide.
Remember that PMI states that you will be tested on concepts that may not be found in the PMBOK Guide but they do not tell you where you can find those concepts. You shouldn’t let this sway your confidence, though, as many concepts and techniques are built on basic building blocks. You will most likely be able to understand the question, analyze the information and pick the best answer. If not, then there is only one thing to do: pick an answer and then simply move one and relax.
Remember, everyone will probably encounter one or more of these questions. The key is not to panic, keep your cool and do your best. If you’ve studied properly, you’ll pass the test!