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': 'What percentage of cold thyroid nodules are malignant \nSelect and explain. \nA. 70-80%, B. 50-60%, C. 40-50%, D. 10-20%', 'role': 'user'}, {'content': "Answer: D \nExplanation: Ans. is 'd' i.e. 10-20%", 'role': 'assistant'}]