JAMB Biology 2018 Paper

Concept:Osmosis is the movement of water from a less concentrated solution to a more concentrated solution through a selectively permeable membrane.Explanation:In the setup, solution $Y$ is more concentrated than solution $X$.Water molecules move by osmosis from solution $X$ (lower solute concentration) into solution $Y$ (higher solute concentration).As water enters $Y$, the volume and level of solution $Y$ rise.As water leaves $X$, the volume and level of solution $X$ fall.This movement continues until the solute concentrations on both sides tend to become equal.Answer:The correct option is D. The level of $Y$ would rise, $X$ would fall.