A data consists of 100 observations $$x_{1},x_{2},... x_{100}$$. If $$\sum_{i=1}^{100}(3x_{i}+17)^{2}=22500$$ and $$\sum_{i=1}^{100}(3x_{i}+17)= 900$$, then the standard deviation of $$x_{},x_{2},... , x_{100}$$ is

A

10

B

8

C

4

D

5