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: Gynaecology & Obstetrics
[{'content': 'Risk factors for Endometriosis are all except \nSelect and explain. \nA. Nulliparity, B. Smoking, C. Early menarche, D. Alcohol consumption', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Smoking is protective factor for Endometriosis.', 'role': 'assistant'}]