The brightness controls on a display primarily adjust which level?

The brightness controls on a display primarily adjust the white level, which refers to the overall brightness of the display and how bright the white areas appear. When you increase the brightness, you are essentially raising the light output of the display, making the brightest parts of the image more luminous. This adjustment allows for better visibility in brightly lit environments and helps ensure that information displayed, particularly in the highlights, is clear and legible.

Black level adjustments relate to the darkness of the darkest parts of an image, affecting contrast but not overall brightness. Chroma level refers to the saturation or intensity of colors, while hue adjusts the actual color itself rather than brightness. Therefore, when discussing brightness controls, the primary focus is on how they impact the display’s response to white levels, making "White Level" the most accurate answer.