Final answer:
Shape is the art element that stands out due to its boundary, created with lines or color changes.
Step-by-step explanation:
The element of art that is defined as an area that stands out from the space next to it because of a boundary is shape. Shape is created using lines, colors, or a change in texture to form a visible boundary that distinguishes it from the surrounding space.
Shapes can vary from geometric, which have a predictable form, to organic, which have a more free form and are less predictable in outline.