Place where birds are kept

Answer: Option D

One word substitute is Aviary.

Zoo: an establishment which maintains a collection of wild animals, typically in a park or gardens, for study, conservation, or display to the public.
Apiary: a place where bees are kept; a collection of beehives.
Armoury: a place where weapons are kept.
Aviary: a large cage, building, or enclosure for keeping birds in.