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 effective temperature of ‘comfort zone’ is \nSelect and explain. \nA. 69 – 76°F, B. 83 – 85°F, C. 77 – 80°F, D. 86 – 90°F', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]