This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cell Wall Synthesis Inhibitors, Subject name: Pharmacology
[{'content': 'All of the following are true regarding penicillin G except:- \nSelect and explain. \nA. Probenecid decreases it duration of action, B. It is active against gram positive organisms, C. It Splits into 6 amino penicillanic acid by amidase, D. It acts by inhibiting cell wall synthesis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Probenecid inhibits tubular secretion and increase the duration of action of penicillin G Penicillin G is sho acting. To overcome this problem: Benzathine and procaine group can be added to penicillin G to make it long acting. Benzathine penicillin G is longest acting penicillin. Probenecid can be administered with penicillins. Former inhibits the tubular secretion. Penicillins have wide therapeutic index. A high initial dose can be used.', 'role': 'assistant'}]