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': 'On TVS which of the following shape of cervix indicates preterm labour: \nSelect and explain. \nA. T, B. Y, C. U, D. O', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]