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: Social & Preventive Medicine
[{'content': 'The optimum floor space recommended per adult person in a house \nSelect and explain. \nA. 101–150 sq.ft., B. 70–90 sq. ft., C. 151–200 sq.ft., D. 201–250 sq. ft.', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Optimum floor space recommended per adult person in a house: 70 – 90 sq.ft. (7 – 9 sq.m.)', 'role': 'assistant'}]