Question

_________is the darker region of the shadow.

Answer 1

Regions of a shadow: Umbra and penumbra

Umbra:

1. The region between the opaque object and the screen, which does not receive any light and is the darkest, is called the umbra.
2. It forms the central part of the shadow.

Penumbra:

1. The region of partial darkness that receives some light is called penumbra.
2. It lies at the periphery of umbra.

Hence, Umbra is the darker region of the shadow.