Final answer:
When all parts of a circuit are composed of conducting materials, the circuit is said to be closed. In a closed circuit, electric current can flow freely as there are no gaps or breaks in the path.
Step-by-step explanation:
When all parts of a circuit are composed of conducting materials, the circuit is said to be closed. In a closed circuit, electric current can flow freely as there are no gaps or breaks in the path. This allows for the proper functioning of electrical devices connected to the circuit.
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