Which of the following colors is NOT a primary color?

The choice of green as the answer is informed by the understanding of color theory, particularly how primary colors function within the color wheel. Primary colors—red, yellow, and blue—are the foundational colors that cannot be created by mixing other colors together. They serve as the building blocks for creating all other colors.

Green, on the other hand, is classified as a secondary color because it is formed by mixing two primary colors: blue and yellow. Thus, it does not belong to the set of primary colors. Recognizing which colors are primary and which are secondary is essential for art and design, as it informs how to create a broader spectrum of colors through mixing. This foundational knowledge is a key aspect of understanding color interactions and their applications in various fields, including mortuary science, where color theory can sometimes play a role in presentation and aesthetics.