If you are taking a multiple choice test, there is an art to them.
1) If you have two answers that are opposites, usually one of those in the answer.
2) The longest answer is mostly likely the correct one, especially if it is exceeding longer than the other ones. Remember, people have to make up wrong answers, so they tend to keep them short.
3) When in total doubt, "C."
4) If two answers are correct and you have "all of the above" that is the one you choose.
5) If it is NRRPT and "Compton's Scattering is a choice, that is most likely the answer (they love CS).
6) Responses that use absolute words, such as "always" or "never" are less likely to be correct than ones that use conditional words like "usually" or "probably."
7)"Funny" responses are usually wrong.

Look for grammatical clues. If the stem ends with the indefinite article "an," for example, then the correct response probably begins with a vowel.
9) Look for verbal associations. A response that repeats key words that are in the stem is likely to be correct.
i.e Who is responsible for the electrical maintenance?
a) electrician b) mechanic c. rad con, d) QA