Which of the following factors can directly affect the sway angle?

The sway angle of a vessel refers to the side-to-side motion that can be experienced in response to various external and internal factors. Each of the mentioned factors contributes to this motion, making the comprehensive understanding of their impacts essential.

The vessel's size and cargo weight are critical because they influence the ship's center of gravity and metacentric height, affecting the stability and motion behavior in the water. Heavier cargo can lower the center of gravity, potentially increasing stability but also may increase sway due to the inertia of the weight shifting when the vessel rocks.

Weather conditions and sea state play a significant role as well. High winds and waves can create forces that cause the ship to sway more dramatically. The severity of the waves can directly impart motion to the hull, leading to greater sway angles.

The ship's speed and maneuvering techniques also directly affect sway. A faster-moving vessel may experience increased lateral forces, especially when turning or navigating in confined waters. Effective maneuvering techniques may help mitigate excessive sway by adjusting the ship's orientation to the waves.

Given that all these factors independently and collectively influence sway angle, selecting "All of the above" is correct, as each factor listed has a direct effect on a vessel's lateral motion.