When an opinion poll calls residential telephone numbers at random, only 20% of the calls reach a live person. You watch the random dialing machine make 15 calls. Let X be the number of calls that reach a live person.
Does X have a binomial distribution?

A. No, the calls are not independent.
B. No, the calls are independent, but each one has more than two possibilities.
C. Yes, the calls are independent, each one has two possibilities, and the probability of reaching a live person is the same for each call.
D. No, the calls are independent, each one has two possibilities, but the probability of reaching a live person is not the same for each call.