Which type of circuit allows multiple devices to turn on and off independently?

A parallel circuit is the correct answer because it allows multiple devices to connect to the same power source independently. In a parallel configuration, each device has its own separate path to the power supply. This means that if one device is turned off or malfunctions, it does not affect the operation of the others. Each device can be controlled individually, enabling them to be turned on and off without impacting the others in the circuit. This is particularly useful in household electrical systems where appliances or lights may need to function independently.

In contrast, a series circuit connects all devices in a single pathway. This configuration means that if one device is turned off or fails, it interrupts the flow of electricity to all devices in the circuit, causing them all to turn off. A combination circuit features aspects of both series and parallel configurations, but it does not guarantee the same level of independent control as a purely parallel circuit. A closed circuit refers to a complete electrical loop that allows current to flow but does not specify the arrangement of the devices. Therefore, the parallel circuit is best suited for independent operation.