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: Orthopaedics
[{'content': 'Which of the following is seen in osteoporosis - \nSelect and explain. \nA. Low Ca, high PO4, high alkaline phosphatase, B. Low Ca, low PO4, low alkaline phosphatase, C. Normal Ca, normal PO4, normal alkaline phosphatase, D. Low Ca, low PO4, normal alkaline phosphatase', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Serum calcium, phosphate and alkaline phosphatase are normal in osteoporosis.', 'role': 'assistant'}]