Which of the following defines a conductor in electrical terms?

A conductor in electrical terms is defined as a material that allows the flow of electric charge, typically electrons. This characteristic is crucial for the functioning of electrical circuits, as conductors provide a pathway for current to travel from one point to another. Common examples of conductors include metals such as copper and aluminum, which have numerous free electrons that facilitate this flow.

The other options describe different concepts. While the first option refers to thermal conductivity, it is not specific to electrical current. The third option describes a capacitor, which is indeed a device that stores electrical energy but does not conduct electricity. The fourth option mentions an insulator, which conversely blocks electrical flow rather than allowing it. Therefore, the most accurate definition of a conductor is its ability to transmit electrical current.