Illinois Cosmetology Practice Exam 2026 – All-in-One Guide to Master Your Licensing Test!

The hair straightener is specifically designed to smooth and straighten hair by using heat. This tool typically consists of two flat plates that are heated and applied to sections of hair, effectively removing curl and frizz to create a sleek, polished look. Hair straighteners operate by breaking down the hydrogen bonds in the hair, allowing the hair to be reshaped into a straighter form as it cools.

In contrast, a curling wand is built to create curls and waves, while hot rollers are used to add volume and curls to the hair through a different mechanism of heat application. A crimper is designed to create waves or bends in the hair rather than to straighten it. Therefore, the hair straightener stands out as the tool specifically intended for achieving straight hair, which makes it the correct answer for this question.