What is the meaning of the prefix in-?

• A. Out of
• B. Too much
• C. In
• D. Not, in

Answer: (D)

The prefix in- has two common functions: it can negate a word, giving a meaning like not or opposite (as in inactive or incomplete), and it can indicate position inside or movement into (as in indoor or inhale). Because it covers both senses, the best description is “Not, in,” which acknowledges its negation role as well as its inward/inside sense. The standalone meaning “in” would miss the negation use, while the other options don’t capture the negation function and thus don’t fit the broad way in- is used in vocabulary.