Question

which portion of the flagellum spins during the swimming motion? all three components the hook and filament just the filament just the basal body

Explanation:

In bacterial flagellum structure, during swimming motion, the hook (which connects the basal body to the filament) and the filament (the long, whip - like structure) spin as a unit, driven by the basal body's motor function. The basal body is more of a motor - like structure that generates the rotational force, and the hook and filament rotate together. So the portion that spins is the hook and filament.

Answer:

The hook and filament