What is the primary function of a ship's keel?

The primary function of a ship's keel is to provide stability and structural integrity to the vessel. The keel is the backbone of the ship, running along the bottom from the bow to the stern. It helps to ensure that the vessel remains upright and balanced in the water, which is crucial for maintaining stability during sailing. A well-designed keel not only aids in preventing the ship from rolling excessively in waves but also contributes to the overall strength of the vessel's hull, allowing it to withstand the pressures and forces encountered at sea. This structural integrity is essential for the safety and performance of the ship, making the keel a vital component in naval architecture.

The other options, while related to the general functioning or equipment of a ship, do not accurately describe the primary role of the keel. The keel is specifically designed to enhance stability and support the overall structure, differentiating it from components responsible for propulsion, storage, or navigation.