13. The evolution of eukaryotic cells most likely involved (A) endosymbiosis of an aerobic bacterium in a larger host cell-the endosymbiont evolved into mitochondria (B) anaerobic archaea taking up residence inside a larger bacterial host cell to escape toxic oxygen-the anacrobic bacterium evolved into chloroplasts (C) an endosymbiotic fungal cell evolving into the nucleus (D) acquisition of an endomembrane system and subsequent evolution of mitochondria from a portion of the Golgi