I am stuck please help

The answer is flagellum

Explanation: Prokaryotes are single-celled organisms belonging to the domains Bacteria and Archaea, and flagellum is a whip-like structure that allows a cell to move. They are found in all three domains of the living world: bacteria, archaea, and eukaryota, also known as protists, plants, animals, and fungi. Also The primary role of the flagellum is locomotion, but it also often has function as a sensory organelle, being sensitive to chemicals and temperatures outside the cell. Flagella are organelles defined by function rather than structure. Flagella vary greatly.

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