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': 'A 28 yrs old lady, is suspected to have polycystic ovarian disease. Sample for testing LH and FSH are best taken on the following days of menstrual cycle: \nSelect and explain. \nA. 4-Jan, B. 10-Aug, C. 13-15, D. 24-26', 'role': 'user'}, {'content': "Answer: B \nExplanation: LH and FSH are maximum during pre ovulatory period. So the best option provided here is 8-10 days. Ref: Shaw's Textbook of Gynaecology, 12th Edition, Page 77 ; The Menstrual Cycle: Physiology, Reproductive Disorders and Infeility By Michel Ferin, Raphael Jewelewicz, Michelle P. Warren, 1993, Page 5 ; Reproductive Endocrinology and Infeility: Integrating Modern Clinical and Laboratory Practice By Douglas T. Carrell, 2010, Page 147", 'role': 'assistant'}]