Definition: You are given a question on philosophy. You are also given 4 answer options (associated with "A", "B", "C", "D"), out of which only one is correct. You need to answer the question by selecting the correct option. You should only answer with the choice letter, not the whole answer.
Input: Aquinas argues that the end of every action is:
(A)some desire. (B)some pleasure. (C)some good. (D)some emotional state.

C