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': 'All the following drugs undergo metabolism by acetylation EXCEPT \nSelect and explain. \nA. INH, B. Hydralazine, C. Procainamide, D. phenytoin', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans) d) (Phenytoin) Ref: KDT 6th ed pg25Compounds having amino or hydrazine residue are conjugated wiyh the help of acetyl Co enzyme - A which include drugs like sulphonamides, INH, PAS, hydralazine, clonazepam, procainamide Phenytoin is metabolised in liver by hydroxylation and glucoronide conjugation.', 'role': 'assistant'}]