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 drugs act on cell membrane EXCEPT : \nSelect and explain. \nA. Nystatin, B. Griseofulvin, C. Amphotericin B, D. Polymyxin B', 'role': 'user'}, {'content': 'Answer: B \nExplanation: It acts by affecting mitosis but the exact mechanism is not known.', 'role': 'assistant'}]