What is the function of a component that controls the flow of current?

The function of a component that controls the flow of current is precisely to regulate or manage how much current passes through it. This is essential in electrical circuits to ensure that the devices connected receive the appropriate amount of current for their operation. Such components can include resistors, transistors, or even switches, depending on the specific application. By controlling the current flow, these components help protect devices from overcurrent conditions, enable modulation of signals, and assist in creating stable and efficient electrical systems.

The other options, while relevant to different functions within an electrical circuit, do not pertain to the primary role of controlling current flow. Giving off light pertains to light-emitting diodes or bulbs, supplying electrical energy refers to batteries or power sources, and converting electrical energy into radio waves describes transmitters or antennas. Each of these has its specific purpose, distinct from the function of simply controlling current flow in a circuit.