My husband, though, who writes multiple choice tests, tells me that if you have no clue at all, you should look for the answer that is the longest and most detailed. It is probably the right one. Shorter answers and especially answers that contain spelling or grammar mistakes are less likely to be correct, because the people writing the test put more thought into the right answer than the decoys.

Also, even if you have no idea about the question, always read all the answers carefully and see if you can rule some out. Eg. you might not know who the generals in the civil war were, but you KNOW they weren’t John Lennon and Ringo Starr, right?