This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Autonomic nervous system, Subject name: Pharmacology
[{'content': 'All are cholinergic agents except I \nSelect and explain. \nA. Galantamine, B. Donepezil, C. Tacrine, D. Memantine', 'role': 'user'}, {'content': "Answer: D \nExplanation: Refer kDT 6/e p 472,473 Donepazil, rivastigmine, gallantamine and tacrine are cholinergic drugs( due to inhibition of cholenesterase enzyme)useful for Alzheimer's disease Memantine is an NMDA blocker, used for Alzheimer's disease", 'role': 'assistant'}]