Explain the process of equalization during descent.

During descent, equalization is essential for preventing discomfort and potential injury due to the pressure changes experienced underwater. As a diver descends, the external water pressure increases, which can cause the pressure in the air-filled spaces of the body, particularly the ears, to become lower than that of the surrounding water. To equalize, divers must actively balance the pressure in their ears with that of the surrounding water. This is typically achieved by techniques such as the Valsalva maneuver, where the diver pinches the nose and gently blows, or the Frenzel maneuver, which utilizes the throat to equalize.

This process is crucial because if pressure is not equalized, it can lead to barotrauma, resulting in pain or injury to the eardrum or other structures of the ear. Regular equalization during descent allows the diver to enjoy a safe and comfortable dive experience. The other options relate to different aspects of diving safety and physiology but do not pertain directly to the act of equalizing pressure in relation to descent.