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': 'Lumbar sympathectomy is of value in the management of: \nSelect and explain. \nA. Intermittent claudication, B. Distal ischaemia affecting the skin of the toes, C. Arteriovenous fistula, D. Back pain', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]