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': 'The biochemical marker for primary hyperparathyroidism is \nSelect and explain. \nA. Hypercalcemia, B. Hypophosphatemia, C. Increased alkaline phosphatase levels, D. Increased ACTH', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]