Find the Standard Deviation $\sigma$ , for the Binomial Distribution Which Has the Stated Values

Multiple Choice

Find the standard deviation, $\sigma$ , for the binomial distribution which has the stated values of n and p . Round your answer to the nearest hundredth.
n=503 ; p=0.7

A) $\sigma = 14.40$
B) $\sigma = 10.28$
C) $\sigma = 7.87$
D) $\sigma = 13.55$