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': 'GH secretion is: \nSelect and explain. \nA. Greater in early morning, B. Greater in evening, C. Increased on prolonged fasting, D. Stimulates B-\xadcells of pancreases directly', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]