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': 'To decrease PPH, drug used prophylactically is : \nSelect and explain. \nA. Oxytocin, B. Methergin, C. Progesterone, D. Prostaglandin', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Methergin', 'role': 'assistant'}]