An engineer for an automotive manufacturer is studying the occurrence of breakdowns in assembly lines. From 5 years of data he finds that the number of breakdowns in any 10-minute interval is independent of the number of breakdowns in any other 10-minute interval of time. The average number of breakdowns has been fairly constant over the past year. Let N be the number of 10-minute intervals in which no breakdowns occur over a randomly selected day. The distribution of the N is
A. hypergeometric
B. binomial
C. negative binomial
D. Poisson
E. exponential