Which NEC-related conclusion is true for receptacles?

• A. They must be listed.
• B. They must be marked with the manufacturer's name or identification.
• C. They must be marked with their voltage and amperage rating.
• D. All of the above

Answer: (D)

Receptacles must meet safety and traceability requirements in the NEC, which means they need to be listed by a recognized testing laboratory and carry markings identifying the manufacturer and the device's electrical ratings. Listing shows the device has been tested and approved for use in electrical installations. The manufacturer's name or identification allows you to trace replacement parts and warranty, while the voltage and amperage rating tells you that the receptacle is suitable for the circuit and load it will serve. Together these requirements ensure installations are safe, compatible, and up to code, so the correct conclusion is that all of these conditions apply.