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': 'Which of the following anti-epileptic agents causes the reversible side-effect of gingival hyperplasia? \nSelect and explain. \nA. Ethosuximide, B. Phenobarbitone, C. Sodium valproate, D. None of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]