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: By “animal motion,” Hobbes means:
(A)involuntary operations such as heartbeat and breathing. (B)instinctive behavior, such as nursing young. (C)irrational behavior. (D)all voluntary behavior.

D