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
Main site of peripheral vascular resistance is 
Select and explain. 
A. Pre-Capillary arterioles, B. Pre-Capillary sphincters, C. Capillaries, D. Windkessel vessels
A: Pre-Capillary arterioles
Answer: A: Pre-Capillary arterioles 
Explanation: Arterioles are the chief site of vascular resistance.