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
Mean, Median and mode all are zero. The type of distribution is ? 
Select and explain. 
A. Standard normal, B. Negatively skewed, C. Positively skewed, D. J shaped
A: Standard normal
Answer: A: Standard normal 
Explanation: Ans. is 'a' i.e., Standard normal