When taking multiple choice tests you should be looking for the best choice out of the options. Read each question carefully and all the alternative answers. In the first pass through the test answer the obvious questions. Then go back and consider the ones you are unsure of. Sometimes having gone through the exam will suggest new ideas to you, or remind you of something you have learned.
For questions where you are still unsure of the correct answer, here are some strategies:
Go back when you are done and check your test again by covering up the answers and retaking it. Try doing it reverse order so that you mind doesn't automatically go down the same path. Don't be afraid to change an answer. As you do a test you should be getting increasingly ``into it'' and remembering more of the material.
On my tests there is no penalty for guessing, so don't leave any answers blank. Also, if you feel a question is ambiguous, or subject to interpretation you can write the explanation for your answer in and this will be taken into account when the test is graded.