Which of the following contributes to a diver’s overall buoyancy?

The body's composition, specifically the ratio of body fat to lean mass, significantly influences a diver's overall buoyancy. Fat tissue is less dense than water, which means that individuals with higher body fat percentages will tend to be more buoyant and float more easily. In contrast, lean muscle mass is denser than water, which can contribute to increased sinking potential. Therefore, a diver with more fat mass will have a different buoyancy characteristic compared to a diver with a higher percentage of muscle mass. This relationship makes it crucial for divers to understand their buoyancy and adjust their gear accordingly to achieve proper balance underwater.

The other factors listed, while they may affect a diver's experience, do not directly contribute to buoyancy in the same way. For instance, the color of a wetsuit does not impact buoyancy; it primarily influences visibility and thermal comfort. Time spent underwater relates more to the diver's gas consumption and physiological effects rather than buoyancy. Lastly, the depth of the dive affects external pressure but does not change the diver's overall buoyancy in terms of body composition. Hence, body composition is the key factor that determines a diver's buoyancy.