The purification method where solid substances change from solid to vapor state without passing through the liquid state is called as which of the following?

Commonly used techniques for the separation and purification of organic compounds are: (a) Crystallisation, (b) Sublimation (c) Distillation (d) Fractional distillation (e) Steam distillation (f) Azeotropic distillation (g) Differential extraction and (h) Chromatography