Suppose you are scientist and you want to use a confidence interval to estimate the true mean number of times a person in your city blinks each day. If the number of times a person blinks each day is normally distributed, how many measurements must you have in order to be sure the sampling distribution of is normal?

A. n > 30
B. n ≥ 10
C. np 10 and n(1-p) > 10
D. np ≥ 10 and n(1-p) ≥ 10
E. np 5 and n(1-p) ≥ 5
F. Any n will do.