Among the processes listed, condensation involves a release of energy. When a gas transitions into a liquid, such as when water vapor in the air cools down and forms droplets, it releases energy in the form of heat.
This release occurs because the molecules in the gas are moving rapidly and have high energy. As these molecules lose energy, they slow down and come closer together to form a liquid. This process is exothermic, meaning that it produces heat. In contrast, melting (solid to liquid) and boiling (liquid to gas) require energy input, while sublimation (solid to gas) also consumes energy. Therefore, condensation is the correct answer.