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': 'Treatment of 42-year-old obese man with blood glucose 450 mg, urine albumin 2+ Sugar 4+ Ketone 1+ is - \nSelect and explain. \nA. Insulin, B. Glibenclamide, C. Glipizide, D. Metformin', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]