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
Healing below knee joint is slow because of 
Select and explain. 
A. Decreased subcutaneous fat, B. Increased movement, C. Weight bearing, D. Poor vascularity
D: Poor vascularity
Answer: D: Poor vascularity 
Explanation: D i.e. Poor vascularily