Which of the following is NOT a type of noun?

The correct answer is C because an adjective is a part of speech that describes or modifies a noun, rather than being a type of noun itself. Adjectives provide additional information about nouns, such as describing qualities, quantities, or states.

In contrast, common nouns refer to general items or classes of items (like 'dog' or 'city'), while proper nouns specify particular names of people, places, or organizations (like 'John' or 'New York'). Abstract nouns refer to ideas, qualities, or conditions that are not tangible (like 'happiness' or 'freedom'). Each of these types of nouns serves specific roles in language, whereas adjectives fulfill a different grammatical function. This distinction clarifies why C, being an adjective, does not belong to the category of nouns.