Convection is a method of energy transfer that involves the movement of fluids (which includes gases and liquids). In this process, warmer areas of a fluid rise while cooler areas sink, creating a circulation pattern that transfers heat.
The correct choice highlights an observable phenomenon: warm air rising in a room. When the air is heated, it becomes less dense than the cooler air around it, causing it to rise. As it rises, it displaces cooler air, which then gets heated in turn, creating a continuous cycle of heat distribution. This movement of air is a classic example of convection in action.
Other options illustrate different forms of energy transfer. Heating a metal rod in a flame (first option) involves conduction, where heat is transferred directly through a solid material. Light from a lamp spreading across a table (third option) is an example of radiation, as light energy travels through space without the need for a medium. The last option, ice melting in warm water, primarily involves conduction as the heat from the water transfers to the ice, causing it to melt. Thus, the phenomenon of warm air rising is specifically indicative of convection.