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: Pathology
[{'content': 'Prion disease is cuased by \nSelect and explain. \nA. Misfolding of proteins, B. Denaturation of protein, C. Reduced formation of proteins, D. Excess formation of proteins', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]