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': "Drug therapy used in treatment of Wernicke's encephalopathy : \nSelect and explain. \nA. Diazepam, B. Disulfiram, C. Thiamine, D. Cynocobalamine", 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]