Which statement about listing changes when an assembly is modified is true?

• A. Listing remains valid
• B. Listing is automatically updated
• C. Listing is invalidated (even if new materials meet specs)
• D. Listing is unaffected if the new components are similar

Answer: (C)

A listing certifies a specific assembly with defined components and installation details. When you modify that assembly, the performance and behavior the listing evaluated are no longer the same, so the original listing no longer guarantees safety or compliance. Even if the new materials meet their specs, the configuration has changed, and the listing must be re-evaluated and updated (or a new listing issued) to reflect the modified assembly. In practice, you’d need to consult the listing body to confirm whether substitutions are allowed; absent explicit authorization, the modification invalidates the current listing.

That’s why remaining options aren’t correct: a listing isn’t automatically kept valid just because components are similar or meet specs, and it isn’t automatically updated without a formal re-evaluation.