During summer, when the snow melts, the water level of the Yukon River increases. If the water level of the river increased by 72 centimeters in 8 days, what is the water level increase rate in centimeters per day?
A. 9 centimeters per day
B. 12 centimeters per day
C. 11 centimeters per day
D. 8 centimeters per day