What type of curl creates fullness by turning the ends of the hair under?

The type of curl that creates fullness by turning the ends of the hair under is known as a cascade curl. This technique involves wrapping sections of hair around a roller or curling iron in a way that adds volume and creates a soft, bouncy effect, particularly at the ends. The cascade curl is characterized by its ability to lift the hair away from the scalp while also turning the ends under, giving it a polished and voluminous appearance.

The other options represent different curling techniques or styles. Barrel curls typically create curls that have more defined shapes without necessarily turning the ends under in a way that emphasizes fullness. Wand curls are often used to create beachy, loose waves rather than focusing on turning the ends under. Pin curls are flat curls formed by twisting sections of hair and pinning them to the scalp, and while they can create volume, they do not specifically focus on turning the ends under in the same way that cascade curls do.