This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Aerial disorders, Subject name: Surgery
Diabetic gangrene is due to: 
Select and explain. 
A. Ischemia, B. Increased blood glucose, C. Altered defense by host and neuropathy, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: Diabetic gangrene is related to: - Trophic changes from peripheral neuropathy - Ischemia as a result of microangiopathy and macroangiopathy (atherosclerosis) - Low resistance to infection because of excess sugar in the tissues