Given a Binomial Distribution with N Trials and Probability P $\le$

Given a binomial distribution with n trials and probability p of a success on any trial,a conventional rule of thumb is that the normal distribution will provide an adequate approximation of the binomial distribution if

A) np $\le$ 5 and n(1- p) $\le$ 5
B) np $\ge$ 5 and np(1 -p) $\ge$ 5
C) np $\ge$ 5 and n(1 -p) $\ge$ 5
D) None of these choices.