This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General physiology, Subject name: Physiology
[{'content': 'Total body water is \nSelect and explain. \nA. 40% of body weight, B. 20% of body weight, C. 10% of body weight, D. 60% of body weight', 'role': 'user'}, {'content': "Answer: D \nExplanation: In the average young adult male, 18% of the body weight is protein and related substances, 7% is mineral, and 15% is fat. The remaining 60% is water.(REF: GANONG'S REVIEW OF MEDICAL PHYSIOLOGY 23rd EDITION page no.2)", 'role': 'assistant'}]