Which of the following describes an unsaturated solution?

An unsaturated solution is characterized by the presence of less solute than the maximum amount it can dissolve at a given temperature. This means there is still capacity within the solution to dissolve more solute. In various contexts, if you were to add more solute to an unsaturated solution, it would continue to dissolve until it reaches saturation, where no additional solute can be dissolved at that temperature.

In contrast, a saturated solution contains the maximum amount of solute that can be maintained in solution under the current conditions (typically temperature and pressure), and a supersaturated solution holds more solute than is normally possible, often achieved by altering the conditions. The definition of an unsaturated solution distinctly highlights its ability to still accept more solute before reaching saturation, which is the key point that makes this description accurate.