The endosymbiotic theory says that precursor eukaryotic cells acquired mitochondria by endosymbiosis with a _____ ancestor, and others gained photosynthetic ability from endosymbiosis with a _____ ancestor.
A)protozoan, algae B)archaea, cyanobacteria C)rickettsial, cyanobacteria D)helminth, algae E)None of the choices are correct.