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': 'Treatment of choice in cold nodule of thyroid \nSelect and explain. \nA. Sub-total thyroidectomy, B. I-131, C. Hemithyroidectomy, D. Excision of nodule', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]