A swimming pool with a capacity of 20,000 gallons is being drained. The table models the volume of the water in the pool, y, after a given number of hours, x.


x (hours) 0 1 2 3 4 5
y (gallons) 20,000 19,000 18,000 17,000 16,000 15,000
Which type of model would best fit the data, and why?
A. The data models an exponential decay function because the volume decreases by 1,000 gallons per hour.
B. The data models an exponential decay function because the volume increases by 1,000 gallons per hour.
C. The data models a linear function because the volume decreases by 1,000 gallons per hour.
D. The data models a linear function because the volume increases by 1,000 gallons per hour.