This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Central Nervous system, Subject name: Pharmacology
[{'content': "True statement about drugs used in Parkinsonism is: \nSelect and explain. \nA. Amantadine is a cholinergic drug, B. Vitamin B6 enhances the L-Dopa action, C. COMT inhibitors prolong the action of L'-dopa, D. None", 'role': 'user'}, {'content': 'Answer: C \nExplanation: Both entacapone and tolcapone enhance and prolong the therapeutic effect of levodopa-carbidopa in advanced and fluctuating PD Ref KD Tripati 8th ed.', 'role': 'assistant'}]