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': 'Mean + 1.96 SD include following % of values in a distribution: September 2012 \nSelect and explain. \nA. 68%, B. 99.50%, C. 88.70%, D. 95%', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans: D i.e. 95% 96 is the approximate value of the 97.5 percentile point of the normal distribution used in probability and statistics. 95% of the area under a normal curve lies within roughly 1.96 standard detions of the mean, and due to the central limit theorem, this number is therefore used in the construction of approximate 95% confidence intervals.', 'role': 'assistant'}]