Which description matches a grounded shield coax cable?

• A. A coaxial cable for audio signals
• B. Electrical cable of one or more insulated conductors enclosed by a common conductive layer
• C. A wire used for grounding only
• D. A fiber optic cable

Answer: (B)

Shielded coax cables have a central conductor that carries the signal, an insulating layer around it, and a surrounding conductive shield that is usually tied to ground. The shield serves two jobs: it blocks external electromagnetic interference and provides a stable reference so the signal impedance stays consistent. The description matches this structure by stating the cable is an electrical one composed of insulated conductors encased by a common conductive layer, which is exactly how a coax’s shield surrounds the inner conductor. In contrast, the other options describe different kinds of cables or purposes (like a grounding-only wire or a fiber optic cable) and don’t capture the shielding around a signal-carrying conductor.