Select the option that can be used as a one-word substitute for the given group of words.

The nest of a squirrel, typically in the form of a mass of twigs in a tree

Drey

The answer is drey.

• Hole is a hollow place in a solid object.
• Burrow is a hole or tunnel dug in the ground by an animal.
• Lair is a wild animal's resting place, especially a den or cave.

The word drey is the best fit for the given group of words because it refers to the nest of a squirrel, typically in the form of a mass of twigs in a tree.