Question

the darkest part of a shadow is closest to what? the object casting the shadow the edge of the paper the light source

Explanation:

The darkest part of a shadow (umbra) forms where light from the source is completely blocked by the object. So, it's closest to the object casting the shadow. The edge of the paper is irrelevant, and the light source is where light originates, not where the darkest shadow is near.

Answer:

A. the object casting the shadow