The correct answer is (B) Inhabitant; resident; someone or something that frequents a place. Also, anyone or anything admitted to, or adapted to, a new place, country, residence, condition, etc.

Denizen comes from Middle English denisein, Old French denzein.

Examples of use:

• Nature has adapted the denizens of the deep to life in a dark environment.
• She had no desire to intermingle with the denizens of this smoke-filled bar.