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': 'The ovulatory period corresponds to : \nSelect and explain. \nA. 14 days before menstruation, B. The day of menstruation, C. Increase in basal temperature, D. 14 days atter menstruation', 'role': 'user'}, {'content': 'Answer: A \nExplanation: 14 days before menstruation', 'role': 'assistant'}]