This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Chemotherapy, Subject name: Pharmacology
[{'content': 'One of the following is not penicillinase susceptible? \nSelect and explain. \nA. Amoxicillin, B. Penicillin G, C. Pieperacillin, D. Cloxacillin', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Penicillinase-resistant penicillins Methicillin, Cloxacillin. ESSENTIALS OF MEDICAL PHARMACOLOGY page no.721', 'role': 'assistant'}]