This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nutrition and health, Subject name: Social & Preventive Medicine
[{'content': 'RDA of calcium in normal adult male is? \nSelect and explain. \nA. 600 mg, B. 400 mg, C. 1200 mg, D. 100 mg', 'role': 'user'}, {'content': "Answer: A \nExplanation: RDA of calcium in normal adult male is 600mg/dl.REF.PARK'S TEXTBOOK OF PREVENTIVE AND SOCIAL MEDICINE.Editon-21.Page no.-588 table no.29", 'role': 'assistant'}]