The sentence that contains a collective noun is letter D: The legislature met in secret session. Nouns are names of a person, animal, place, event, etc. It could be proper or common noun. Common nouns are names of general items and you find them everywhere you go. These words are not usually capitalized, except if it is the starting word in a sentence. Proper nouns on the other hand are more specific names and they are capitalized. Collective nouns are nouns denoting quantity.