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': 'True about presence of bacteria in female reproductive tract is all except \nSelect and explain. \nA. Anaerobes predominate and outnumber aerobic species., B. Upper reproductive tract is sterile., C. Function of vaginal bacterial colonization is unknown., D. Presence of bacteria does not indicate active infection.', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Female upper reproductive tract is not sterile.', 'role': 'assistant'}]