Connecticut Barber Licensure Practice Exam

Using a toner on hair primarily serves to enhance or neutralize color tones, which is why this choice is the correct one. Toners are typically used after bleaching or dyeing hair to adjust the shade by either adding richness or removing unwanted hues. For example, a toner can help eliminate brassy or yellow tones in blonde hair, lending it a cooler, more balanced appearance. This process allows for a more customized coloration, as toners can come in various shades designed to suit different hair color needs.

The other options do not accurately describe the primary function of a toner. While curly hair can be styled with various products, toners do not have a curling effect. Cleaning the hair is generally the role of shampoos and cleansers, not toners, which are more about color correction and enhancement. Additionally, adding volume is typically associated with styling products, not toners, which focus on adjusting hair color rather than its texture or body.