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
[{'content': 'Healing below knee joint is slow because of \nSelect and explain. \nA. Decreased subcutaneous fat, B. Increased movement, C. Weight bearing, D. Poor vascularity', 'role': 'user'}, {'content': 'Answer: D \nExplanation: D i.e. Poor vascularily', 'role': 'assistant'}]