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
The effective temperature of 'comfo zone is'? 
Select and explain. 
A. 69-76deg F, B. 77-80deg, C. 83-85deg F, D. 86-90deg F
B: 77-80deg
Answer: B: 77-80deg 
Explanation: Ans. is `b' i.e. 77-80deg F