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: Physiology
The neurons may get irreversibly damaged if exposed to significant hypoxia for : 
Select and explain. 
A. 8 min, B. 2 min, C. 30 sec, D. 15 sec
A: 8 min
Answer: A: 8 min 
Explanation: A i.e. 8 min