Study the illustration. The small blue spheres represent water molecules.

To determine the direction of water movement across the membrane, we need to consider the principles of osmosis. Osmosis is the movement of water molecules through a semi-permeable membrane from an area of lower solute concentration (higher water concentration) to an area of higher solute concentration (lower water concentration) to achieve equilibrium.

Without specific information about the concentrations of solute on sides A and B, here’s how you would analyze it:

- If side A has a higher concentration of solute than side B, water will move from B to A.
- If side B has a higher concentration of solute than side A, water will move from A to B.
- If both sides have equal concentrations of solute, there will be no net movement of water.

Based on this understanding, you would choose one of the three options depending on the solute concentrations provided in the illustration. If you know the concentrations or have additional context, please share it, and I can help you determine the exact answer.