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': 'Which of the following is NOT true about penicillins ? \nSelect and explain. \nA. Penicillin V is absorbed orally, B. Benzathine penicillin is short acting penicillin, C. Cloxacillin is β–lactamase and acid resistant, D. Ampicillin is not resistant to β–lactamases', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]