In hair color treatment, what does "color mixing" involve?

Color mixing is a fundamental practice in hair coloring that involves the combination of different shades to create a unique, custom color tailored to the client's preferences. This process allows the stylist to achieve a specific hue that may not be readily available in a single shade, facilitating personalization and the ability to address individual client needs. By blending various tones, a stylist can produce a color that complements the client's skin tone, hair type, and overall style, achieving a more nuanced and appealing result.

This approach involves knowledge of color theory, as understanding how different shades interact with one another is crucial for creating desired outcomes. The other options mentioned do not capture the essence of color mixing; for example, using a single color for highlights does not involve blending different shades, and applying two separate colors without combining them does not achieve the custom blending aspect that color mixing embodies.