What is the main function of a switch in an electrical circuit?

The main function of a switch in an electrical circuit is to open or close the circuit. This action allows the flow of electrical current to be controlled. When the switch is closed, it creates a complete path for the current to flow, enabling devices within the circuit to operate. Conversely, when the switch is opened, it interrupts the current flow, effectively turning off the connected devices.

This ability to control the circuit is fundamental in electrical systems, as it permits users to turn devices on and off as needed without having to physically disconnect them. The other options, such as regulating voltage, reducing current flow, or increasing resistance, involve different components or mechanisms in a circuit and are not the primary function of a switch. A switch specifically serves to manage the connection within the circuit itself.