This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Aetiological factors, Subject name: Gynaecology & Obstetrics
[{'content': 'Most common cause of CA cervix: \nSelect and explain. \nA. HPV 6 and 18, B. HPV16andl8, C. HPV 6, D. HPV 6 and 11', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. (b) HPV 16 and 18Ref. Shaws 15th ed, / 952* Women with STD, HIV infection, herpes simplex virus 2 infection, human papilloma virus (HPV) infection (16, 18, 31, 33) or condylomata have a high predisposition to cancer.* Of these, HPV is now considered the most important cause, most commonly cause by HPV 16 and 18* Most HPV infection 16, 18 are symptomless in young women and clear within 2 years.* Persistent infection is the cause of cancer of the cervix in 70-90% cases.', 'role': 'assistant'}]