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': "The effective temperature of the 'comfo zone' is- \nSelect and explain. \nA. 69-76 o F, B. 77-80 oF, C. 83-85 oF, D. 86-90 oF", 'role': 'user'}, {'content': "Answer: B \nExplanation: Comfo zones: In deg C of corrected effective temperature Pleasant and cool 20 Comfoable and cool 20-25 Comfoable 25- 27 (77-80F) Hot and uncomfoable 27-28 Extremely hot 28+ Intolerably hot 30+. Park's Textbook of Preventive and Social Medicine, 25th Edition, Pg 792", 'role': 'assistant'}]