This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Normal Menstruation, Abnormal Menstruation, Menopausal Physiology and forsight of conception, Subject name: Gynaecology & Obstetrics
[{'content': 'Time required for ovulation from the onset of LH surge is \nSelect and explain. \nA. 12 hours, B. 24 hours, C. 36 hours, D. 48 hours', 'role': 'user'}, {'content': 'Answer: C \nExplanation: From the onset of the LH surge, it takes 34-36 hours and from the peak it takes 10-12 hours to ovulate. The midcycle LH surge is responsible for a dramatic increase in local concentrations of prostaglandins and proteolytic enzymes in the follicle. These substances progressively weaken the follicular wall and ultimately allow a perforation to form.', 'role': 'assistant'}]