Where can GMDSS regulations pertaining specifically to U.S.-flag vessels be found?

Correct Answer: Option D — These are located in 47 CFR Part 80.

47 CFR Part 80 contains the comprehensive FCC rules governing the operation of maritime radio services in the United States. This includes specific technical standards, licensing requirements, and operational procedures for GMDSS-equipped vessels, ensuring consistency with international IMO requirements and domestic regulatory mandates for U.S.-flagged commercial shipping.