Prewired raceway assemblies may only be used under what condition?

Prewired raceway assemblies are assemblies that combine raceways with wiring already installed, and their use is regulated to ensure safety and compliance with electrical standards. The correct condition for their use is that they must be specifically permitted in the National Electrical Code (NEC). The NEC provides guidelines and safety standards that apply to various electrical installations, so using prewired raceway assemblies without specific permission could lead to safety hazards and code violations.

This option reflects the necessity of adhering to regulatory standards put forth by the NEC, ensuring that any installation is safe, reliable, and compliant with established electrical practices. The other options do not take into account the regulatory framework set by the NEC, which governs where and how various wiring methods and materials can be used.