This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardiovascular system, Subject name: Pathology
Approximate time, at the end of which the quantity, of ATP within ischemic cardiac myocytes is reduced to 10% of original is 
Select and explain. 
A. <2 minutes, B. 10 minutes, C. 20 minutes, D. 40 minutes
D: 40 minutes
Answer: D: 40 minutes 
Explanation: ATP decreases to 10% of its intial level in 40 min Robbins 9 th edition page no. 380