The central cytoplasmic region of a prokaryotic cell containing nucleic acids is called:

In prokaryotic cells (such as bacteria), there is no membrane-bound nucleus. Instead, the genetic material (DNA) is located in an irregularly shaped region of the cytoplasm called the nucleoid. The nucleoid contains the circular DNA along with associated proteins, but it is not enclosed by a nuclear membrane. The nucleus and nucleolus are features of eukaryotic cells, while plastids are organelles found in plant cells. Hence the correct term for this region in prokaryotes is the nucleoid.