Which of the following is made up of 12 major colors?

The correct answer identifies the color wheel, which is comprised of 12 major colors. A color wheel visually represents the relationships between different colors, typically arranged in a circular format. The 12 major colors commonly included are the primary colors (red, blue, yellow), secondary colors (orange, green, purple), and tertiary colors (such as red-orange, yellow-green, etc.). This arrangement helps in understanding color mixing and color harmony, serving as a vital tool for artists and designers when creating color palettes or working with color schemes.

The other options do not accurately represent a set of 12 major colors. A color palette refers to a selection of colors used for a specific purpose, which may vary widely and does not have a fixed structure. A color spectrum refers to the continuum of colors, typically seen in a gradient and not limited to a specific number of major colors. A color gradient illustrates a smooth transition between colors, rather than distinct major colors. Hence, the color wheel is uniquely defined by its arrangement and inclusion of 12 major colors.