In a contrast ratio, which colors are compared?

The correct answer is based on the fundamental principles of contrast ratios, which are used to measure the difference in brightness between two colors. In the context of a contrast ratio, the comparison is specifically made between the brightest color, which is white, and the darkest color, which is black. This allows for a clear understanding of how visible or legible content is against its background, often essential for design considerations in various applications, including website accessibility and graphic design.

The brightest and darkest colors create the maximum possible contrast, making this comparison the most effective for determining visibility and readability. When assessing visual content, achieving an appropriate contrast ratio is crucial for ensuring that the intended message is communicated clearly to the audience.

Other options focus on specific categories or types of colors, which do not provide the broad measure necessary for establishing a contrast ratio. Understanding contrast primarily revolves around the extremes of light and dark, emphasizing the importance of the white-black comparison in practical applications.