In Amphibians, Why Does the Reabsorption of NaCl Depend on the Permeability

In amphibians, why does the reabsorption of NaCl depend on the permeability of the tubule wall to water?

A) Water movement allows the ATP to function more effectively.
B) Water movement creates the concentration gradient for Cl to move passively.
C) Water permeability allows the solutes to move more effectively.
D) Water must move first before any of the solutes can move.