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': 'Carcinoma cervix is caused by HPV : \nSelect and explain. \nA. 18, 21, 33, B. 16, 18, 21, C. 16, 18, 33, D. 16, 21, 33', 'role': 'user'}, {'content': 'Answer: C \nExplanation: 16, 18, 33', 'role': 'assistant'}]