This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Disorders in Menstruation, Subject name: Gynaecology & Obstetrics
[{'content': 'Which of these is diagnostic of menopause? \nSelect and explain. \nA. Serum FSH >40, B. Serum LH >20, C. Serum FSH <40, D. Serum estradiol <30', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans, is a, i.e. Serum FSH > 40Ref: Shaw's Textbook of Gynecology 15th/ed, p62Diagnostic Criteria for Menopause* Estrogen (E2) low at 10-20pg/mL* Estrone (E1) - 30-70pg/mL* E2/E1 < 1* Urine FSH >40IU/L", 'role': 'assistant'}]