__ is the transition directly from a solid to a gas.

Sublimation is the process through which a substance transitions directly from a solid state to a gas state without first becoming a liquid. This phenomenon occurs under specific conditions, often involving low pressure and sufficient energy, which allow the solid particles to gain enough energy to break free from their fixed positions in the solid structure. A common example is dry ice, which is solid carbon dioxide that sublimates to gas at room temperature, bypassing the liquid phase entirely.

Other processes listed do not match this description: deposition refers to the direct transition from a gas to a solid, evaporation involves a liquid transforming into a gas, and condensation is the conversion of a gas into a liquid. Understanding these terms and their distinctions helps clarify the states of matter and the phase changes that substances can undergo.