How does line help identify different surfaces in a scene?

It can show different texture and direction

The governing concept is descriptive line work. Artists vary the length, spacing, thickness, direction, continuity, and repetition of marks to suggest how a surface looks or behaves. Short broken strokes may suggest rough bark, flowing curved marks may suggest water, and parallel or soft lines may suggest cloth or a smooth plane. Thus, option A is correct because line can communicate both surface texture and directional structure. Option B is the opposite of the purpose: varied marks help distinguish surfaces rather than make them identical. Options C and D are also incorrect because line normally makes visual information more readable and is not limited to indicating the physical thickness of paper. Context determines how the marks are interpreted.

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