Which of the following terms defines hair that is characterized by a smooth texture and allows for easy manipulation?

The term that defines hair characterized by a smooth texture and that allows for easy manipulation is fine hair. Fine hair has a smaller diameter and is generally softer, which contributes to its smoothness. This smoother, softer quality often makes it easier to style and manipulate compared to other hair types, allowing for greater versatility in hair cutting and styling techniques. The ease of manipulation is especially noticeable when working with finer strands, as they tend to hold styles more easily and can be shaped with less resistance.

Coarse hair, in contrast, is thicker and tends to have a rougher texture, often requiring more effort to manipulate and style. Medium hair falls somewhere between fine and coarse but does not specifically embody the characteristics of smoothness and ease of manipulation to the same extent as fine hair. Vellus hair, often referred to as "peach fuzz," is soft and fine but is not typically associated with styling or manipulation in the same way that regular hair types are. Thus, fine hair distinctly aligns with the description provided.