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': 'Which of the following is not caused by Chlamydia trachomatis? \nSelect and explain. \nA. Certis, B. Urethritis, C. Vulvitis, D. Epididymitis', 'role': 'user'}, {'content': "Answer: C \nExplanation: Chlamydia doesn't cause vulvitis. PID is very common.", 'role': 'assistant'}]