Which skill is essential for safe ascent during a dive?

Maintaining positive buoyancy is crucial for a safe ascent during a dive because it allows divers to control their ascent rate effectively. When divers achieve positive buoyancy, they can rise more steadily to the surface without ascending too quickly, which could lead to barotrauma or decompression sickness. A controlled ascent is vital for allowing excess nitrogen to safely leave the body, thus reducing the risk of forming bubbles in the bloodstream.

When divers maintain positive buoyancy, it enables them to focus on their ascent technique, such as using their lungs to manage buoyancy and ensuring they are not holding their breath during the ascent. This skill is essential since an uncontrolled ascent can lead to serious and potentially life-threatening conditions.

The other choices, while relevant to diving in various contexts, do not address the specific skill of ensuring a safe ascent. For example, ascending at a rapid pace can be dangerous, utilizing a dive slate does not impact buoyancy and ascent directly, and descending quickly is contrary to safe diving practices.