To represent color images in RGB color space, which must be specified for each pixel?

In the RGB color space, each pixel's color is represented by specifying the intensity of the three primary colors: red, green, and blue. This model is additive, meaning that these colors are combined together at varying intensities to produce a wide spectrum of colors. For each pixel, the values indicating the intensity of the red, green, and blue components are crucial, as they define the final color that the pixel will display.

For instance, if a pixel has maximum intensity for red and green but no blue, it would display yellow. If all three component values are at their maximum, the result is white. Conversely, if all values are at their minimum, the resultant color is black. This precision in specifying the red, green, and blue components allows digital images to reproduce the vast arrangements of color perceived by the human eye.

The other options, while related to color theory, do not define the specific mechanism of how colors are represented in the RGB model. Brightness, contrast, and saturation refer to adjustments of images rather than the specification of individual pixel color values. Hue, lightness, and color are terms more relevant to HSL (Hue, Saturation, Lightness) color models, not RGB. Lastly, primary and secondary colors