The National Electrical Code defines the requirements for what aspect of electrical systems?

• A. Electrical wiring, including metal boxes
• B. Fire alarm signaling protocols
• C. Lighting color temperature
• D. Energy metering standards

Answer: (A)

The main idea here is safety rules for putting in electrical systems. The National Electrical Code sets the requirements for wiring and the equipment used in electrical installations, including how conductors are run, what kinds of boxes and enclosures are allowed, how box filling is calculated, how circuits are protected with overcurrent devices, and grounding practices. In short, it governs electrical wiring and the components involved to keep installations safe.

That’s why the correct choice is electrical wiring, including metal boxes. The other topics—fire alarm signaling protocols, lighting color temperature, and energy metering standards—are covered by different codes and standards (for example, fire signaling typically falls under NFPA 72, lighting specifications under lighting standards, and metering under other electrical/energy standards).