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': 'Cervical incompetence is characterised by : \nSelect and explain. \nA. Cerclage operation done, B. 2nd trimgster aboion, C. Premature rupture of mombrane, D. All', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. is a, b and c i.e. 2nd trimester aboion; Premature rupture of membrane; and Cerclage operation done', 'role': 'assistant'}]