Which of the following is one of the four basic design principles?

Contrast is one of the four basic design principles because it helps to create visual interest and emphasis by highlighting differences between elements in a design. When two elements are contrasted, such as light against dark or large against small, it draws the viewer's attention and helps them to quickly understand the hierarchy and organization of information. This is essential in graphic communication, as it allows for clear messaging and guides the viewer's focus.

In design, contrast can be applied in various ways, such as in color, size, shape, and texture. Effective use of contrast not only enhances readability but also contributes to the overall aesthetics of the design, making it more engaging.

While complexity, detail, and brightness are important aspects that can inform a design, they do not fundamentally constitute one of the core principles that guide the overall effectiveness and clarity of visual communication in the same way that contrast does.