Which component of a roller curl is referred to as the circle?

The correct answer is the curl, which is referred to as "the circle" in the context of roller curls. In hairstyling, particularly when using rollers, the curl is the actual formation that results from the wrap around the roller. It represents the pattern of the hair that creates the desired wave or curl, and visually, it is circular in shape when assessed from above the roller.

Understanding the distinct components of a roller curl is crucial for stylists. The base is the area of the scalp where the roller is placed, while the stem is the section of hair between the base and the curl that determines the placement and the type of curl. The end is the tip of the hair that wraps around the roller. Each of these elements plays a role in how the final style appears, but the curl is specifically denoted as the "circle" due to its rounded shape as the hair wraps around the roller.