This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Medicine
[{'content': 'The best marker to diagnose thyroid related disorders is- \nSelect and explain. \nA. T3, B. T4, C. TSH, D. Thyroglobulin', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Answer is option 3 TSH The enhanced sensitivity and specificity of TSH assays have greatly improved laboratory assessment of thyroid function. Normal TSH excludes primary abnormalities of thyroid mostly. Ref Harrison 19e /p2283', 'role': 'assistant'}]