Which colors are primarily used in offset printing?

In offset printing, the primary colors used are cyan, magenta, yellow, and black, often referred to as the CMYK color model. This model is specifically created for the printing process, where these four colors can be combined in various ways to produce a wide spectrum of colors. Each color represents a specific ink used in the printing process, allowing for precise color mixing and reproduction.

Cyan, magenta, and yellow are the three subtractive primary colors, and when mixed together in different proportions, they can create a broad range of hues. Black is added to enhance the depth and detail of the printed images, as well as to produce darker tones that cannot be achieved with the three colors alone.

This color model is foundational in the world of printing, making option C the correct choice since it accurately reflects the standard colors used in offset printing.