How does line separate an object from the background?

By making the object's boundary clear

The governing concept is the contour or outline. A line placed around the edge of an object establishes its visible boundary and helps the viewer distinguish the figure from the surrounding background. Differences in position, thickness, value, or continuity can further strengthen that separation, although an outline need not always be equally dark or complete. Therefore, option A is correct because making the object’s boundary clear is the direct function described. Option B uses sound, which is not produced by a visual line. Option C concerns the physical support rather than the depicted relationship between figure and ground. Option D is impossible because lines and colours do not create smell. Artists may sometimes omit an outline and allow contrast, overlap, or value changes to imply an edge, but the question asks how line performs the separation; clarifying the boundary is the appropriate answer.

This is a Class 9 Art Education question. Chapter: Elements of Art. Topic: Line.