The Potentiometric Surface of an Artesian Aquifer Is

The potentiometric surface of an artesian aquifer is:

A) the boundary between the artesian aquifer and an overlying confining layer.
B) the difference in elevation between the area of recharge and the area of discharge.
C) the level to which the water in the area of discharge would rise in the absence of friction.
D) the difference in groundwater potential between water in the area of discharge and water in the area of recharge.