Read the entire sentence and decide if it contains any errors. Try and identify the problem, if you are able. If you know it is a subject-verb disagreement, you can easily narrow down your answer choices.
Read all the options, except for "E." You can skip "E" because it is the same as the original, and doing so will save you time.
Eliminate all options that are obviously wrong or that change the meaning of the sentence.
Read the sentence with the answer you think is correct in your head. If it sounds correct, circle the answer. If the original sentence sounds correct and doesn't require improvement, circle "E."