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: Surgery
Peripheral nerves can withstand ischemia upto ? 
Select and explain. 
A. 30 minutes, B. 1 hour, C. 2 hours, D. None
D: None
Answer: D: None 
Explanation: Ans. is 'None'