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': 'In osteoporosis there is -a) Decrease in absolute amount of bone massb) More common in malec) Radiographs show normal bone densityd) Hormonal replacement therapy \nSelect and explain. \nA. ad, B. c, C. ac, D. ab', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]