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:a) 1st trimester abortionb) 2nd trimester abortionc) Premature rupture of membraned) Circlage operation done \nSelect and explain. \nA. bcd, B. acd, C. ac, D. bd', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]