Certain protozoa engulf cyanobacteria (photosynthetic bacteria)and maintain a given number of the cyanobacteria even when they divide.The protozoa divide only after the cyanobacteria have doubled their number.The cyanobacteria excrete glucose that the protozoa use for energy.This is a good example of
A) parasitism by protozoa. B) how protozoa consume particulate food. C) establishment of an endosymbiotic relationship. D) symbiosis between two microorganisms. E) convergent evolution.