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: Dental
[{'content': 'Draining abscess by cutting a window in the bone is \nSelect and explain. \nA. Hiltons method, B. Trephination, C. Marsupialisation, D. Odontectomy', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]