BOTH INTERNATIONAL & INLAND According to the Navigation Rules, all of the following are engaged in fishing EXCEPT a vessel __________.

Correct Answer: Option C — trolling

Rule 3(d) defines a "vessel engaged in fishing" as one using gear that restricts maneuverability, such as nets, trawls, or lines. It explicitly excludes trolling, as trolling lines do not restrict a vessel's maneuverability enough to warrant special status under the Rules.