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: Unknown
[{'content': 'Which malignancy would occur in long standing multinodular goiter ? \nSelect and explain. \nA. Papillary Carcinoma, B. Follicular Carcinoma, C. Anaplastic Carcinoma, D. Medullary Carcinoma', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Incidence of follicular carcinoma is high in endemic goitrous areas, with long standing multinodular goiter, possibly owing to persistent TSH stimulation.\nDominant or rapidly growing nodules especially in longstanding goiters should always be subjected to aspiration cytology.', 'role': 'assistant'}]