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': 'Feaures of medullary carcinoma thyroid: \nSelect and explain. \nA. Arises from parafollicular cells, B. Amyloid stroma is present on histology, C. Diarrhea occurs, D. All', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans is All "Some tumours are familial, possibly accounting for 10-20% of all cases."- Bailey Total Thyroidectomy is the treatment of choice for patients with MTC because of high incidence of multicentricity, the more aggressive course and RAI therapy usually being not effective.', 'role': 'assistant'}]