Question

The lipids in the cytoplasmic membrane of bacteria and ________ contain ester linkages, while the cytoplasmic membrane of ________ contain ether linkages.

Answer 1

I believe the correct answer is D, Eukarya/Archea.
Bacteria are single-celled organisms which are prokaryotic and neither plants nor animals. Their plasma membrane (cytoplasmic membrane) contains a phospholipid bilayer (like other cell membrane) and thus acts to regulate and control entry of materials in and out of the cells. These lipids in the plasma membrane of both bacteria and eukaryotes contains ester linkages while the membrane of organisms in kingdom archaeabacteria (archaea) contains ether linkages.

Answer 2

Fungi are single-celled or multicellular organisms with nuclei and membrane-wrapped organelles with cell walls made of chitin.
Archaea on the other hand are organisms that have no cell nucleus or any other membrane-bound organelles in their cells.
The lipids in the cytoplasmic membrane of bacteria and Archaea contain ester linkages, while the cytoplasmic membrane of Fungi contain ether linkages.