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': 'All are used for cervical ripening, except : \nSelect and explain. \nA. Ergometrine, B. Oxytocin, C. Stripping of membranes, D. Prostaglandins', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ergometrine', 'role': 'assistant'}]