This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
[{'content': 'Following are gastrointestinal hormones except \nSelect and explain. \nA. CCK, B. GIP, C. Motilin, D. Chymotrypsin', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Chymotrypsin is an enzyme. Others are all hormones.', 'role': 'assistant'}]