What does it mean to "trim" a boat?

Trimming a boat refers specifically to the process of adjusting the angle of the outboard motor or drive to optimize the boat's performance on the water. This adjustment helps to achieve the best possible hydrodynamic efficiency, ensuring that the boat rides smoothly and remains stable, which can improve speed and fuel efficiency. Proper trimming can also enhance control and maneuverability by adjusting how the boat interacts with the water's surface, thereby minimizing drag.

The other options do not accurately reflect the term "trimming" in the context of boating. Checking fuel levels is related to managing onboard resources, securing items is about safety and organization, and adjusting sails pertains specifically to sailing vessels rather than powerboats. Each of those actions is important for overall vessel operation but does not convey the specific meaning of trimming in the context of enhancing boat performance.