Here's the breakdown:
* Prokaryotes: These are single-celled organisms that lack a nucleus and other membrane-bound organelles. Examples include bacteria and archaea.
* DNA: Prokaryotes store their genetic information in a single, circular chromosome located in a region called the nucleoid.
* Ribosomes: These are essential for protein synthesis.
* Flagellum: A whip-like structure used for movement.
While there are many types of prokaryotes, the most common and smallest form that typically possesses all of these features is a bacterium.
It's important to note: Not all bacteria have flagella. Some bacteria are non-motile and lack this structure.
Therefore, the answer to your question is a bacterium.
