Which line can suggest roundness?

Correct answer: Curved line

Correct answer: A, curved line. A line is a visible path made by a moving point. When the path bends smoothly, it can describe the edge of a circle, ball, fruit, or another rounded object. The eye follows this smooth bend and understands roundness even when the object is not shaded. Option A is correct because a curved line directly changes direction continuously and suggests a rounded boundary. Option B, a horizontal line, usually suggests a level surface, rest, or width, not a circular bend. Option C, a vertical line, commonly suggests height, uprightness, or stability. Option D, a diagonal line, usually suggests slant, direction, or movement. These lines can be used inside a rounded drawing, but by themselves they do not communicate roundness as directly as a curve. Memory cue: round forms need lines that turn around them; therefore, think “roundness means curve.”