23. Theenergy added by a pump to the liquid passing through it is often referred to as the total head, which is equal to the total suction head of the liquid when it enters the pump subtracted from the total discharged head of the liquid when it leaves the pump. With the total discharge and suction heads of 10 m and – 0.5 m, what is the total head of the pump?
(A) 20 m
(B) 10.5 m
(C) 9.5 m
(D) 5 m