This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Skeletal system, Subject name: Radiology
[{'content': 'The gold standard for the diagnosis of osteoporosis is - \nSelect and explain. \nA. Dual energy X-ray absorptiometry, B. Single energy X-ray absorptiometry, C. Ultrasound, D. Quantitative computed tomography', 'role': 'user'}, {'content': 'Answer: A \nExplanation: According to the osteoporosis guidelines for diagnosis and treatment, dual X-ray absorptiometry (DXA) represents the "gold standard" for diagnosis of osteoporosis and fracture risk prediction.', 'role': 'assistant'}]