Effective test preparation includes:

a. studying the "right" material

Correct. Studying the "right" material = studying facts, figures, concepts that your professor considers important. This information comes from his/her lectures; your textbook; handouts provided in class; supplemental readings; laboratory exercises; and homework and other course assignments. Questions included in previous tests from your class give you a clue as to what material a professor considers important material. Additionally, a professor will sometimes indicate in class that information will be on a test. If a professor keeps old test on reserve, ensure that you review these. If you are still unsure about what is the "right" material to study, ask your professor.