A shape can set off from its surroundings using changes in:

a. Value [lightness or darkness]
b. color [chroma or hue]
c. texture
d. all of the above

D would probably be the best answer.

d. all of the above

To determine how a shape can stand out from its surroundings, changes in value, color, and texture can be used. Let's break down each of these elements:

a. Value: Value refers to the relative lightness or darkness of a color. By using contrasting values, such as a dark shape against a light background or vice versa, a shape can clearly stand out and create a visual separation from its surroundings.

b. Color: Color can be used to differentiate a shape from its surroundings through changes in chroma (color intensity or saturation) or hue (specific color or shade). By selecting colors that contrast with the surrounding colors, a shape can become more visually prominent.

c. Texture: Texture refers to the tactile quality or look of a surface. By incorporating different textures within a shape, it can create an interesting contrast with the surrounding area, making it more distinguishable.

Thus, using changes in value, color, and texture together or individually can help a shape stand out from its surroundings.