Which type of pencil is more useful for creating dark shading?

Correct answer: Soft pencil

The governing concept is the relationship between pencil hardness and tone. A soft pencil releases more graphite onto the paper and can produce a dark, rich mark with moderate pressure, so option C is correct for deep shading. A very hard pencil generally creates a lighter, sharper line, while a white pencil lightens marks and a mechanical pen is not a normal graphite-shading choice.