Which type of mixture can be separated by crystallisation?

The correct option is D Solid - liquid homogeneous mixture
Crystallisation is used to separate pure solid in the form of crystals from its solution. Therefore, we need solid-liquid homogeneous mixtures (which is also known as solution), to carry out crystallisation process. During crystallisation, the excess solute present at a particular temprature, separates out of solution in the form of crystals.