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: Social & Preventive Medicine
[{'content': 'About standard Normal curve all is true except \nSelect and explain. \nA. Area = 1, B. Mean and Median = 1, C. Bell shaped, D. S.D. = 1', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]