In which of the following hair design techniques is a small section of hair held taut with one hand, while the other hand slides the brush from ends to the base?

Back brushing, also known as "vintage" or "teasing," is the technique where a small section of hair is held taut with one hand, and the other hand uses a brush to slide from the ends of the hair toward the base. This method helps create volume and texture at the roots, resulting in a fuller appearance. It’s particularly useful for adding body and lift to hairstyles, making it a commonly utilized technique in various hair designs.

In contrast, pin curling involves rolling sections of hair and securing them with pins; it does not involve brushing. Blow drying is a method of using hot air to dry hair and can also add volume, but it does not involve the specific action of brushing from ends to base while holding the hair taut. Straightening refers to the process of using heat tools to make hair sleek and smooth, which focuses on the overall style rather than the specific brushing technique described.