Which characteristic distinguishes organisms in kingdom Archaebacteria from organisms in kingdom Eubacteria? A. Most organisms in kingdom Archaebacteria are single-celled, while only some organisms in kingdom Eubacteria are single-cell. B. Organisms in kingdom Archaebacteria are rod shaped, and organisms in kingdom Eubacteria are only cocci or spiral shaped. C. Most organisms in kingdom Archaebacteria live in extreme environments, while most organisms in kingdom Eubacteria live in moderate environments. D. Organisms in kingdom Archaebacteria have circular DNA, and organisms in kingdom Eubacteria have linear DNA.