Answer:
I think it is C. How thin or thick it is
Explanation: Line quality is also called line weight and simply put, refers to the thickness or thinness of the line. Lines may become wider or thicker in areas where the object itself is thicker. Or lines may become thicker to help indicate a light source. Lines in areas of shadow may be thicker. Range in line quality heightens descriptive potential: you can describe textures, movement, light, space, etc. Using many different kinds of lines in your drawing can also add visual interest. Even when the subject or content of a drawing is not readily recognizable, varying line quality can imply space, movement, light, and so on.
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