Answer:
Prokaryotes.
Explanation:
Most of the Eukaryotes most likely to evolve from the Prokaryotes. Prokaryotes are basically unicellular organisms that lack internal membrane-bound structures. So, they do not carry nucleus and generally have a single chromosome. Most of them have a cell wall outside the plasma membrane, which is a thin layer of lipid that completely surrounds the cell. Prokaryotes reproduce by binary fission method.
Alright cool... and saw what..?
Answer: parasitism possibly< this is all i had its a goat
Oxygen has to be the answer because if plants and animals use it they both need these things