Why is equalization important during descent?

Equalization is crucial during descent because it helps prevent ear injuries caused by pressure changes. As a diver descends, the pressure surrounding them increases, which affects the air pressure in the middle ear. If the pressure in the ear is not equalized with the surrounding water pressure, it can lead to discomfort, pain, or even serious injuries like ear barotrauma. By equalizing, divers can gently balance the pressure in their ears, allowing for a safe and comfortable descent. This practice is essential for maintaining ear health during diving activities.

The other choices do not directly relate to the primary concerns a diver faces during changes in pressure. For instance, enhancing swimming speed or improving visibility may be considerations for diving, but they do not address the critical need to protect against pressure-related injuries. Similarly, while buoyancy is important for diving, equalization specifically targets ear pressure issues that arise during descent.