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': 'Side effects of sclerotherapy in treatment of varicose veins are all except \nSelect and explain. \nA. Skin necrosis, B. Thrombophlebitis, C. Anaesthetic complications, D. Anaphylaxis', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Sclerotherapy does not require anaesthesia.', 'role': 'assistant'}]