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': 'Risk of amniotic fluid embolism is greatest in : \nSelect and explain. \nA. First trimester of pregnancy, B. Second trimester of pregnancy, C. During labour, D. In puerperal period', 'role': 'user'}, {'content': 'Answer: C \nExplanation: During labour', 'role': 'assistant'}]