Two images of the same charcoal drawing are shown, but in different stages. The artist used many types of lines in this picture. Which type of line is not pictured?

A. curved
B. bold
C. spiral
D. vertical

C. Spiral

Explanation:

Although I can't see the picture too clearly, it seems that every other line on the answer choices is present; except a spiral line. Curved lines for shoulders and hair, bold lines with shading, and vertical lines for the neck. Hope this helps.