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': 'Treatment of congenital cyst of head of pancreas - \nSelect and explain. \nA. Total excision, B. Partial excision, C. Marsupialization, D. Observe and medical treatment', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]