This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.N.S, Subject name: Pharmacology
[{'content': 'Drug of choice in drug induced parkinsonism is \nSelect and explain. \nA. Levodopa, B. Benzhexol, C. Selegilline, D. Amantadine', 'role': 'user'}, {'content': 'Answer: B \nExplanation: (Benzhexol) (421-KDT 6th)* Trihexyphenidyl (Benzhexol) is most commonly used drug in drug induced Parkinsonism* "Anticholinergics are the only drugs effective in drug (phenothiazine) induced parkinsonism "Drug used in Alzheimer\'s disease Acetylcholinesterase inhibitors - donepezil, galentamine, rivastigmine, tacrine NMDA receptor antagonists - Memantine', 'role': 'assistant'}]