The answer is C: metaphor.
A metaphor is a figure of speech or rhetorical figure in which two things that would not normally or literally be associated become related in order to expand on the figurative sense of the object that is being compared to something else (in this case Tina is compared to a fox). A metaphor is easily identifiable because it establishes the comparison directly without the use of comparative clauses such as: like (when the word “like” or any synonym is used in the comparison, then we are talking about a simile).