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': 'True regarding AV fistula is - \nSelect and explain. \nA. Leads to cardiac failure, B. Causes local gigantism, C. Can cause ulcers, D. All', 'role': 'user'}, {'content': "Answer: D \nExplanation: Answer 'a' i.e. Leads to cardiac failure; 'b' i.e. Causes local gigantism; 'c' i.e. Can cause ulcers", 'role': 'assistant'}]