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': "Progressive cognitive impairment in Alzheimer's disease is characterized by - \nSelect and explain. \nA. Nominal aphasia, B. Recent memory loss, C. No behavioral abnormalities, D. All", 'role': 'user'}, {'content': "Answer: B \nExplanation: Alzheimer's disease is characterized by early impairment of recent memory.", 'role': 'assistant'}]