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 is 
Select and explain. 
A. Asymmetrical, B. Has mean = 1.0, C. Has variance = 0.0, D. Mean = median = mode
D: Mean = median = mode
Answer: D: Mean = median = mode 
Explanation: Normal distribution :

Is Bilaterally symmetrical.
Mean = median = mode.