The archaebacteria are placed in a different kingdom from the plants and animals. The archaebacteria are the organisms that have certain properties which are not common to the organisms placed in bacteria and eukarya. The group contains methanogens that can produce methane gas. The DNA of these organisms is generally present in a relaxed state or as positively coiled. The cell wall of these organisms does not contain lipids, peptidoglycan, etc. Thus, the correct answer is option D.