What is a plausible explanation for why bacteria lack ether-linked cell membranes?

They need chitin in the cell membranes.
They exchange fluids with the environment.
They do not live in the extreme environments.
They have peptidoglycan in their membranes.

The most plausible explanation for why bacteria lack ether-linked cell membranes is that they have peptidoglycan in their membranes. Peptidoglycan is a polymer made up of sugars and amino acids and it provides structural support to the bacterial cell wall. It is commonly found in the cell walls of bacteria and is responsible for their rigidity. Ether-linked cell membranes, on the other hand, are typically found in archaea, a separate domain of microorganisms that are distinct from bacteria. Archaea often live in extreme environments and their ether-linked cell membranes provide them with greater stability and resistance to harsh conditions. Bacteria, however, have evolved alternative protective mechanisms such as peptidoglycan, which may be more suitable for their specific ecological niches.