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: Surgery
[{'content': 'The histopathologic feature of medullary carcinoma of thyroid is \nSelect and explain. \nA. Anaplasia, B. Mitotic figures, C. Psammoma bodies, D. Amyloid stroma', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]