This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Environment and health, Subject name: Social & Preventive Medicine
[{'content': 'Which of the following is considered an adequate water supply/head/day- \nSelect and explain. \nA. 50-150L, B. 150-200L, C. 200-250L, D. 100-150L', 'role': 'user'}, {'content': "Answer: B \nExplanation: park's textbook of preventive and social medicine 23rd edition *a daily supply of 150-200litres per capita is considered as an adequate supply to meet the needs for all urban domestic purposes .", 'role': 'assistant'}]