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: Psychiatry
[{'content': "A/E are true regarding Alzheimer's disease. \nSelect and explain. \nA. Gradually progressive, B. Abrupt onset acute exacerbation, C. Episodic memory, D. All", 'role': 'user'}, {'content': 'Answer: B \nExplanation: B i.e. Abrupt onset acute exacerbation', 'role': 'assistant'}]