Final answer:
Archaea are prokaryotic organisms that lack a nucleus and other membrane-bound organelles, and they differ from bacteria in their metabolic pathways, cell wall, and membrane composition.
Step-by-step explanation:
The fact that correctly distinguishes the archaea from other organisms is that archaea are prokaryotic (Answer b). Unlike eukaryotic cells, archaea lack a nucleus and other membrane-bound organelles. Archaea have unique characteristics compared to bacteria; for instance, they have different metabolic pathways and their cell walls and membranes are composed differently. Specifically, archaeal cell membranes possess phytanyl units linked to glycerol instead of fatty acids, and some archaeal membranes can be lipid monolayers rather than the typical bilayers found in bacteria and eukaryotic cells.