The correct answer is: C. Card cage
A card cage is a framework in which circuit boards can be mounted. It is typically made of metal or plastic and has slots for the circuit boards to fit into. The card cage provides a way to organize and connect the circuit boards, and it also protects them from damage.
A switch circuit is a circuit that controls the flow of electricity. It is typically made of transistors and other electronic components. A chip is a small piece of semiconductor material that contains electronic circuits. A bar code is a series of black and white bars that represent data.
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