What is the correct way to show inner parts of an object separately using lines?

Drawing inner boundary and division lines within the object

The governing concept is the descriptive use of line: an outline shows the outside boundary, while interior or division lines identify separate parts within that boundary. Drawing suitable inner boundaries can distinguish a lid from a container, panes from a window frame, or petals within a flower. Thus option A is correct because it communicates the structure and relationships of internal sections. Erasing internal details removes the very information the question asks us to show. Darkening only the outside contour may make the silhouette stronger, but it cannot separate inner parts. Filling colour without lines may provide tone, yet it does not necessarily define each section clearly. Internal lines should be placed selectively and should follow the actual structure rather than being added randomly or made equally heavy everywhere.

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