The correct answer is the direct change of a substance from a solid to a gas state.Sublimation is a process in which a solid transforms directly into vapours without changing into liquid.This phenomenon can be seen in camphor or naphthalene balls.In the process snow or ice transforms directly into water vapour without becoming water.Additional Information Deposition - It is the process of conversion of a gas to a solid.Evaporation - It is the process of conversion of a liquid into gas.Fusion/Melting - It is the process of conversion of a solid into a liquid.Condensation - It is the process of conversion of a gas into a liquid.