Which two elements of a triode carry the output current?

A triode vacuum tube consists of three primary active elements inside a glass envelope: the cathode, the control grid, and the plate (also known as the anode). When heated, the cathode emits electrons, which travel through the vacuum to the positively charged plate. The main output current of the tube is this flow of electrons between the cathode and the plate. The control grid sits between them to regulate the flow using an electric field, but it is not intended to carry the main output current itself. The distractors rely on confusing vacuum tube terminology with solid-state terminology. Emitter and collector refer to a bipolar transistor, while source and drain refer to a field-effect transistor.