What is indicated by the term "vessel sinking"?

The term "vessel sinking" specifically indicates that a vessel is taking on water and may be on the verge of submerging. This situation typically arises when the vessel’s buoyancy is compromised due to various factors such as damage to the hull, an influx of water from waves, or failures in the vessel's watertight integrity. When a vessel is reported to be sinking, it is crucial to take immediate action, which may include calling for rescue or attempting to stabilize the vessel to prevent total submersion.

The other options describe different statuses of a vessel but do not accurately reflect the condition of sinking. For example, a vessel being repaired on land suggests it is completely out of the water and undergoing maintenance; a vessel docked safely indicates it is secure and not in immediate danger; and a vessel abandoned does not necessarily imply it is taking on water—it may simply be left without anyone aboard but still afloat.