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: Pharmacology
[{'content': 'All of the following are immunosuppressive drugs EXCEPT : \nSelect and explain. \nA. Cyclosporine, B. Cefaclor, C. Azathioprine, D. Steroids', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Cefaclor is a cephalosporin', 'role': 'assistant'}]