Refer to the Figure Shown

Refer to the figure shown. Assume that the two pistons have the same mass and move without friction, the center membrane in the diagram is permeable only to water, and solutes are shaded according to concentration (the darker the shading, the higher the concentration) .
The piston on the left would move upward if the membrane were permeable to only _______ and the solution on the left was _______ and the solution on the right was _______.

A) Na⁺; 1 M Na⁺; 3 M Cl^‒
B) Cl^‒; 1 M Cl^‒; 3 M Na⁺
C) water and Na⁺; 2 M Cl^‒; 3 M Na⁺
D) Ca²⁺; 1 M Na⁺; 3 M Ca²⁺