Correct option is A
Given
The first n natural numbers are 1, 2, 3,……,n.
Formula Used
Mean (μ) of the first n natural numbers:
μ=nSum of first n natural numbers=2nn(n+1)=2n+1
Variance (
σ2) of the first n natural numbers:
σ2=nSum of squares of first n natural numbers−μ2
Sum of squares=6n(n+1)(2n+1)
Standard deviation (σ):
σ=σ2
Solution