Nice post here on writing good multiple choice questions. Click through for the details.
Test knowledge comprehension, not just recall
Use simple sentence structure and precise wording
Place most of the words in the question stem
Make all distractors plausible
Keep all answer choices the same length
Avoid double negatives
Mix up the order of the correct answers
Keep the number of options consistent
Avoid tricking test-takers
Use ‘All of the Above’ and ‘None of the Above’ with caution
And one closing comment; it should be fairly obvious that learners don’t recall everything you stuff into your training. (You shouldn’t be stuffing it in the first place, right!?) So use the questions to reinforce the topics that you need them to remember.