In which of the following types of solution is the rate of dissociation equal to the rate of crystallization? Concentrated Supersaturated Unsaturated Saturated

In a Saturated solution, the rate of dissociation equal to the rate of crystallization

Explanation:

A saturated solution is one than cannot dissolve any more solute because the solutes inter-molecular spaces are filled with the solute molecules at that temperature. When an attempt is made to dissolve more solute into the solution, the rate at which the solute is dissolved into the solution is equal to the rate at which excess solute is precipitated and crystallized.

a corroding iron, if that's one of your choices