I think it is important to design tests that reflect the material that you covered in class. I also think it is imporant to design tests that use a combination of formats: multiple choice (I affectionately call this format multiple guess), true and false (aka fifty-fifty), and others. In all seriousness, instructors need to be aware of the principles of test design. In addition, I believe that instructors should do item analysis once students take the test; this will show whether or not there were testing issues that compromised the validity and reliability of test questions.