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: Physiology
[{'content': 'The quantity of water lost in expired air each 24 hrs is about \nSelect and explain. \nA. 200 ml, B. 350 ml, C. 600 ml, D. 800 ml', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]