This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
[{'content': 'All of the following statements about phenytoin are true except : \nSelect and explain. \nA. It follows saturation kinetics, B. Anti-seizure activity closely resembles plasma concentration, C. Does not depress CNS, D. Cerebellar degeneration occurs on longterm administration', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]