What aspect of art does 'form' utilize?

The term 'form' in the context of art primarily refers to three-dimensional shapes and structures. It encompasses the physical volume and mass of an object, as well as its spatial relationships with other elements in a piece of art. This understanding includes how the form occupies space and can be perceived from multiple angles, which is crucial in disciplines like sculpture and architecture, where the dimensionality is inherent to the work itself.

In contrast, the other options focus on different artistic concepts. Two-dimensional structure relates to flat compositions, often seen in painting and drawing. Color theory addresses the interplay of colors and their relationships but does not deal with how shapes and volumes occupy space. Textural quality refers to the surface characteristics of an artwork, which can enhance the visual and tactile experience but is separate from the concept of three-dimensional form. Therefore, the correct answer reflects the significance of three-dimensionality in understanding form in art.