Which of the following sentences is most clearly describing a symbol?
a. truth, justice, and honor are all values that superman embodies in his quest for goodness.
b. several times in the movie, characters open a briefcase, but the audience never sees its contents.
c. the fist that the drill sergeant hides behind his back represents the power he has over the men.
d. the phrase "kill your darlings" means to delete unneeded writing from a story.