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: Medicine
[{'content': 'Which of the following is found in primary hypothyroidism - \nSelect and explain. \nA. T3 decrease, T4 decrease, TSH increase, B. T3 decrease, T4 increase, TSH decrease, C. T3 normal, T4 normal, TSH increase, D. T3 decrease, T4 decrease, TSH normal', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]