This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General Pharmacology, Subject name: Pharmacology
[{'content': 'Drugs undergoing acetylation include all except: \nSelect and explain. \nA. Dapsone, B. Metoclopramide, C. Procainamide, D. INH', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B. MetoclopramideAcetylation by N-acetyl transferases (NAT)e.g, S - SulfonamidesH - HydralazineI - IsoniazidP - Procainamide, PASD - DapsoneC - Clonazepam, Caffeine', 'role': 'assistant'}]