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: Pathology
The organ most vulnerable to ischaemia due to shock- 
Select and explain. 
A. Lungs, B. Adrenals, C. Kidney, D. Heart
D: Heart
Answer: D: Heart 
Explanation: The susceptibility of a tissue to hypoxia influences the likelihood of infarction.
Neurons are most sensitive to hypoxia (irreversible changes develop in 3-4 minutes) followed by myocardial cells (irreversible changes develop in 20-40 minutes).
Fibroblasts are amongst the most resistant cells to hypoxia.