Question

Could someone help me with this, please?
The following distribution consists of 19 values. The mean of the distribution is 34, and the standard deviation is 10.

19, 21, 22, 23, 25, 26, 28, 30, 33, 33, 34, 38, 39, 41, 43, 45, 48, 48, 50

Which of the following actions will increase the standard deviation by the greatest amount?

a. Add the value 14 to the distribution for a total of 20 observations.
B. Add the values 41 and 42 to the distribution for a total of 21 observations.
C. Add the values 0 and 1 to the distribution for a total of 21 observations.
D. Add the values 14, 14 and 14, to the distribution for a total of 22

THANK YOU :)