Which statement about the genomes of prokaryotes is correct?

A) Prokaryotic genomes are diploid throughout most of the cell cycle.
B) Prokaryotic chromosomes are sometimes called plasmids.
C) Prokaryotic cells have multiple chromosomes, "packed" with a relatively large amount of protein.
D) The prokaryotic chromosome is not contained within a nucleus but, rather, is found at the nucleolus.
E) Prokaryotic genomes are composed of circular DNA.