Which form of heat does NOT heat the surrounding air?

Radiant heat is a form of heat transfer that occurs without the need for a medium such as air or water. It involves the emission of thermal energy through electromagnetic waves, primarily in the infrared spectrum. This means that radiant heat can transfer energy directly from a hot surface to an object or person without warming the air in between.

In contrast, conduction heat requires direct contact between materials for heat transfer to occur, while convection heat involves the movement of warm air or fluid, which does lead to warming the surrounding air. Supplied air typically refers to heated or cooled air introduced into a space, which directly alters the temperature of the surrounding air. Therefore, radiant heat is unique in that it does not rely on the heating of air, making it the correct answer in this context.