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
The standard normal distribution 
Select and explain. 
A. Is skewed to the left, B. Has variance = 1.0, C. Has standard deviation = 0.0, D. Has mean = 1.0
B: Has variance = 1.0
Answer: B: Has variance = 1.0 
Explanation: Normal Distribution:

Is also known as ‘Gaussian distribution’ or ‘Standard distribution’
Type of distribution: Is the distribution of values of a quantitative variable such that they are symmetric with respect to a middle value with same mean, median and mode, and then the frequencies taper off rapidly and symmetrically on both sides – ‘bell shaped distribution’.