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: Medicine
[{'content': 'Fatal familial insomnia is associated with - \nSelect and explain. \nA. Prion disease, B. Degenerative disease, C. Neoplastic disease, D. Vascular disease', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]