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': 'A 20 year old girl, presents with 9 month history of neck swelling with thyrotoxic  symptoms.  On investigation, increased T4 and decreased TSH with palpable 2 cm nodule was found. Next investigation will be: \nSelect and explain. \nA. USG, B. Thyroid scan, C. Radioactive iodine uptake, D. CT scan', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]