43. Which document shows a vessel's nationality, ownership, and tonnage?

The Certificate of Documentation, issued by the U.S. Coast Guard, establishes a vessel's nationality, ownership, and tonnage. This document, as defined in 46 CFR Part 67, serves as formal proof of a U.S. vessel's legal status and includes key details such as the vessel's name, owner, and tonnage; other options document voyages, cargo, or carriage contracts, and do not fulfill the question's requirements.