This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Physiology
[{'content': 'Ovulation is primarily caused by preovulatory surge of \nSelect and explain. \nA. Estradiol, B. Luteinizing hormone, C. Progesterone, D. Follicle stimulating hormone', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Estrogen levels peak towards the end of the follicular phase. This causes a surge in levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). This lasts from 24 to 36 hours, and results in the rupture of the ovarian follicles, causing the oocyte to be released from the ovary the oviduct.Ref: Ganong&;s review of medical physiology; 24th edition; page no:-406', 'role': 'assistant'}]