What Is the Primary Role for the Na⁺/ K⁺ pump

What is the primary role for the Na⁺/ K⁺ pump?

A) the maintenance of Na⁺ and K⁺ concentrations once inside the membrane
B) the maintenance of Na⁺ and K⁺ concentrations on either side of the membrane
C) to produce ATP while pumping Na⁺ and K⁺ against their concentration gradients
D) to pump Na⁺ and K⁺ down their concentration gradients out of the cell
E) to create a polarized membrane in an excitable cell