This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thyroid Gland, Subject name: Surgery
[{'content': 'The best marker to diagnose thyroid related disorder is: \nSelect and explain. \nA. T3, B. T4, C. TSH, D. Thyroglobulin', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. (c) TSHRef: Schwartz 10th edition Page 1349* TSH assay is the most sensitive and Specific test for diagnosis of hyper and hypothyroidism for optimizing T4 therapy.', 'role': 'assistant'}]