Which of the following describes convection as a form of heat transfer?

Convection is specifically described as the process of heat transfer that occurs in fluids, which includes both gases and liquids. This form of heat transfer is characterized by the movement of the fluid itself. As the fluid is heated, it becomes less dense and rises, while cooler, denser fluid sinks, creating a circulation pattern that facilitates the transfer of heat. This is different from conduction, which occurs through solids and relies on direct contact between materials.

Since convection relies on the movement of fluid rather than direct contact or a material conductor, other options do not accurately represent the nature of convection. For example, while convection can involve some thermal conduction in the process, it does not require a thermal conductor to occur. Additionally, convection is generally more efficient than conduction, making it a faster form of heat transfer in many scenarios. Thus, the identification of convection occurring specifically in gases and liquids encapsulates its defining characteristics accurately.