What problem will occur if every new layer is kept fully opaque while building depth through colour layers?

Correct answer: Lower layers will be covered and layered depth will decrease

The governing concept is transparent layering, often called glazing, in which a thin translucent layer allows some underlying colour to remain visible. If every successive layer is fully opaque, it hides rather than integrates the earlier layers. The image can lose tonal interaction, visual depth, and the sense of accumulated colour. Thus option D is correct. Options A, B, and C do not describe the normal effect of excessive opacity.