Which method is used to purify solids?

Crystallization

The correct answer is option 3. Crystallization

The crystallization method is used to purify solids.

Crystallization is a process that separates a pure solid in the form of its crystals from a solution.

For example, the salt we get from seawater can have many impurities in it. To remove these impurities, the process of crystallization is used.