Ans.
Domain Archaea consists single-celled, prokaryotic microorganisms. These organisms do not have true nucleus and other membrane-bound organelles. They can live in rough and hard conditions, such as salt lakes, hot sringsm and marshlands. Domain Archaea includes both autotrophic (such as Halobacterium) and heterotrophic (such as Pyrococcus).
Thus, the correct answer is option). 'prokaryotic.'