Answer: The correct option for the fill in the blank is Archaea; Bacteria.
Carl Woese gave a system of biological classification called Three domain system. According to this system, life forms are divided into three domains that is Archaea , Bacteria, and Eukarya.
Archaea and Bacteria domain possess the prokaryotic organisms ( like bacteria) whereas Eukarya domain consists of all the eukaryotic organisms ( like plants and animals).
Thus, Archaea and Bacteria is the right answer.
