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': 'First investigation for solitary thyroid nodules is: (Or) Investigation of choice in discrete thyroid swelling is \nSelect and explain. \nA. Thyroid scan, B. CT scan, C. MRI, D. FNAC', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]