Respuesta :
D. flock
A collective noun is a noun/name that is given to a group. For instance, a “crowd” is collective noun because it means a group or gathering of people. A “mob” is a collective noun because it means an unruly group of people. A “flock” is a collective noun because it means a group of birds. “Barn” is simply a common noun. “Loudly” is an adverb.” And, “Canada” is a proper noun.
A collective noun is a word which refers to a collection of things taken as a whole. There for word flock would be your collective noun.