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': "Drug which interferes or hampers the effectiveness of OCP are all except aEUR' \nSelect and explain. \nA. Aspirin, B. Tetracycline, C. Rifampicin, D. Phenytoin", 'role': 'user'}, {'content': 'Answer: A \nExplanation: Aspirin', 'role': 'assistant'}]