Final answer:
The lightness or darkness of a surface in art is known as c) 'value,' which is an element of art defining relative lightness or darkness and allows the creation of depth and mood.
Step-by-step explanation:
The lightness or darkness of a surface in the context of art is referred to as the c) value.
Value is an element of art that allows artists to create the illusion of light by adjusting the relative lightness or darkness of colors or shapes compared to one another. The value scale, which shows the standard variations in tones, includes a spectrum from pure white to dark black, and the various shades of grey in between. High-keyed values are on the lighter end, while low-keyed values denote the darker end. When we add white to a hue, we get a tint of the color, and when we add black, we get a shade. Exploring different values gives artists the ability to portray depth, form, and mood within their artwork.