What is the noun form of the adjective 'necessary'?

• A. Necessary
• B. Necessarily
• C. Necessity
• D. Necessariness

Answer: (C)

Turning adjectives into nouns often uses suffixes to name the quality or state described. For “necessary,” the standard noun form is “necessity,” which means something that must be done or the state of being required. The adjective “necessary” describes something as required, but it does not name a thing, so it isn’t the noun form. “Necessarily” is an adverb, used to describe how something is done or true. A rarer noun form, “necessariness,” exists but is not the common, everyday usage. So the best, widely accepted noun is “necessity.”