Answer: C. The fist the drill sergeant hides behind his back represents the power he has over the men.
A symbol is a mark, a sign, a word, a gesture, an idea or an image that is used to convey an idea or belief. Symbols create links between otherwise very different concepts and experiences. In this case, the best example of the use of a symbol is option C. The symbol in this sentence is the fist the drill sergeant has behind his back. Moreover, the sentence tells us that this is meant to represent the power that he has over men.
