Answer:
A. The data are discrete because there are a finite or countable number of values.
Step-by-step explanation:
In continuous data there are infinite possibilities for the values, on the other hand, discrete data has a limited number of possibilities for its values.
In this case, the number of customers waiting is a discrete value, there is a limit and it will be an integer number. Therefore, the answer is
A. The data are discrete because there are a finite or countable number of values.