Answer:
D. A Poisson Probability Distribution
Explanation:
Poisson Probability Distribution
This is a probability distribution is used in probability theory and statistics to express the probability of a number of events that occur with a known rate or interval of distance, area, volume or time. Specifically, the Poisson probability distribution named after Simeon Denis Poisson, a French mathematician, is used to express probability where events occur one independent of the other.
Comparing this definition with the waiting line situations, one thing is common, arrivals occur independently of other arrivals and this distribution can be described using the Poisson Probability Distribution.