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: Medicine
[{'content': 'Diabetes control is best monitored by \nSelect and explain. \nA. Serum glucose, B. Post prandial blood glucose, C. HbA1AC, D. HbA2AC', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]