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': 'Which of the following is MOST commonly associated with green discharge? \nSelect and explain. \nA. Duct papilloma, B. Duct ectasia, C. Retention cyst, D. Fibroadenoma', 'role': 'user'}, {'content': 'Answer: B \nExplanation: A black or green discharge is usually due to duct ectasia and its complications. Ref: Bailey & Love 25/e, Page 831', 'role': 'assistant'}]