Final answer:
Bacteria and Archaea can be distinguished by their transcription and translation mechanisms due to differences in cell wall composition and membrane lipids.
Step-by-step explanation:
Bacteria and Archaea are most easily distinguished from each other by their D) transcription and translation mechanism. While both Bacteria and Archaea are single-celled, microscopic organisms with some similar structures such as a cell wall, cell membrane, and flagella, they differ fundamentally in their cell wall composition and membrane lipids. Archaea have cell walls that do not contain peptidoglycan and their membrane lipids are based on phytanyl groups. In contrast, bacteria have cell walls with peptidoglycan and membrane lipids composed of fatty acids. This distinct cell wall and membrane composition is tied to differences in their transcription and translation mechanisms.