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: 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: Dual Energy X-ray absorptiometry (DEXA) is the gold standard and investigation of choice for diagnosis of osteoporosis.', 'role': 'assistant'}]