Which technique is useful for showing the effect of a rough surface?

Correct answer: Dry brush technique

The governing concept is texture: the appearance of a rough surface is suggested by broken, uneven deposits of paint rather than a perfectly smooth layer. In dry-brush technique, a brush carrying relatively little wet paint catches the raised areas of the paper or surface and leaves irregular marks. Therefore, option A is correct. An even wash, smooth blend, and wet glaze are designed to produce more continuous or smooth effects, so they are less suitable for rough texture.