What Role Does Na⁺/K⁺-ATPase Play in Salt Excretion by the Shark

What role does Na⁺/K⁺-ATPase play in salt excretion by the shark rectal gland?

A) Na⁺/K⁺-ATPase pumps sodium out and potassium into cells across the apical membrane.
B) Na⁺/K⁺-ATPase pumps sodium into and potassium out of cells across the apical membrane.
C) Na⁺/K⁺-ATPase pumps sodium out and potassium into cells across the basolateral membrane.
D) Na⁺/K⁺-ATPase pumps sodium into and potassium out of cells across the basolateral membrane.