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: Pathology
[{'content': 'FNAC is the least diagnostic in which thyroid carcinoma- \nSelect and explain. \nA. Anaplastic, B. Papillary, C. Follicular, D. Thyroiditis', 'role': 'user'}, {'content': 'Answer: C \nExplanation: FNAC is the best investigation for the diagnosis of all thyroid carcinomas except follicular carcinoma.\nIt cannot differentiate b/w follicular carcinoma and follicular adenoma. The definitive diagnosis of carcinoma is\xa0made when capsular and vascular invasion by the carcinoma is revealed.\n\nImportant features of follicular carcinoma\n\nSecond most common type of thyroid cancer.\nHurthle cells are seen.\nDifferentiated from follicular adenoma by capsular and/or vascular invasion.\nUnlike in papillary carcinoma, lymphatic spread is rare, and vascular invasion is common in follicular cancers.', 'role': 'assistant'}]