Which of the following best describes electrical installations covered by the Code?

The correct choice is that the Code covers all electrical installations. This is because the National Electrical Code (NEC) is designed to establish safety standards for a wide variety of electrical systems, regardless of the type of building or structure. This comprehensive coverage ensures that any electrical installation, whether in residential, commercial, or industrial settings, adheres to specified safety practices, minimizing risks such as fire hazards and electrical shock.

Focusing only on specific types of installations, such as residential or commercial, would leave other important areas unregulated and could lead to significant safety risks. The objective of the Code is to promote overall public safety through adequate standards that apply uniformly across all settings where electrical systems are used. Therefore, the recognition that it covers all electrical installations reflects the Code's commitment to protecting people and property from electrical hazards.