Concept:Ksp is the equilibrium constant for a sparingly soluble salt in a saturated solution.Explanation:At saturation, the salt is in equilibrium with its ions in solution.So Ksp is the product of the concentrations of the dissolved ions, each raised to the power of its coefficient in the balanced equation.It therefore gives the concentration of a solute present in a saturated solution at a given temperature.This concentration represents the maximum amount that can remain dissolved before precipitation begins.Answer:B. To determine the concentration of a solute in a saturated solution.