This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Physiology
Optimal operation theatre temperature should be 
Select and explain. 
A. 21degC, B. 28degC, C. 32degC, D. 37degC
A: 21degC
Answer: A: 21degC 
Explanation: Optimal operation theatre temperature for adults is 21degC and for children is 28degC.