Answer:
Choice B- Ribosomes
Step-by-step explanation:
From the figure of a bacterial (prokaryotic) cell (most probably), The Ribosomes are spiky organelles [Marked as A], that are embedded in the Cytosol [Marked as B] of the cell, bounded by the Cell Membrane (wall) [Marked as C] and the cell moves in all directions with a help of its tail-like structure called Flagellum [Marked as D].