What error may occur if a cube is given round shading?

Its flat planes may become less clear

The governing concept is that shading must agree with the geometry of the form. A cube is made of flat planes meeting at comparatively definite edges. When each face is assigned a clear but related value according to the light direction, the viewer can read the planes and recognise the solid as a cube. Round, smoothly blended shading suggests a continuously curved surface, more like a sphere or rounded object. Therefore option A is correct: the flat planes may lose their visual clarity and the cube may look softened or incorrectly modelled. Option B is too absolute; shading alone does not necessarily erase every edge. Option C confuses tonal modelling with distance from the light, and D is incorrect because shading does not automatically alter proportion.

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