Protobionts are thought to be the first nonliving structures that evolved into living cells.A critical characteristic of a protobiont that is found in both modern day prokaryotes and eukaryotes is

A)internal compartments that subdivide metabolic functions.
B)a boundary membrane that separates external from internal environments.
C)the ability to exclude all organic substances.
D)the ability to fuse with any other protobiont for reproduction.
E)the ability to recognize other protobionts for developmental purposes.