This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General surgery, Subject name: Surgery
[{'content': 'Clostridium difficile infection risk increases on use of \nSelect and explain. \nA. Ciprofloxacin, B. Metronidazole, C. Vancomycin, D. Teicoplanin', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ciprofloxacin increases risk of C.difficile enterocolitis.Metronidazole, vancomycin, teicoplanin are effective agaist C. difficile in cases of pseudomembranous colitis.Ref: Bailey and Love 27e pg: 56', 'role': 'assistant'}]