What kind of lines are useful for showing pointed rocks?

Correct answer: Sharp angular lines

Correct answer: D, sharp angular lines. Pointed rocks have hard edges, corners and sudden changes in direction. Angular lines contain turns or corners, so they can visually suggest the sharp, broken surface of rocks. A is unsuitable because rounded lines usually communicate softness, smoothness or flowing movement. B is too limited: horizontal lines may show direction or stability but cannot by themselves communicate pointed corners. C may be useful for a light or broken mark in another context, but it does not clearly express the strong edges of a rock. D therefore best matches both the physical appearance and the visual feeling of pointed rocks. Memory cue: sharp object, sharp angle; soft object, curved line.