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: Unknown
[{'content': 'Failure of OCP is caused by \nSelect and explain. \nA. Rifampicin, B. Nevirapine, C. Phenytoin, D. AH of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans-D A clinical guide to Contraception Leon speroffDrugs causing failure of OCPRifampicinRifabutinPhenytoinNevirapinePhenobarbitoneTopiramateVigabatrinCarbamazepineEthosuximideGriseofulvin', 'role': 'assistant'}]