This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Disorders of menstruation, Subject name: Gynaecology & Obstetrics
[{'content': 'Average blood loss in normal menstruation \nSelect and explain. \nA. 50 mL, B. 80 mL, C. 100 mL, D. 120 mL', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The duration of menstruation is 4-5 days and the amount of blood loss estimated to be 20-80ml with an average of 35ml. Reference: D.C.DUTTA&;S TEXTBOOK OF GYNECOLOGY; 6th edition; PG NO:82', 'role': 'assistant'}]