The evolution of eukaryotic cells most likely involved
A)endosymbiosis of an oxygen-using bacterium in a larger host cell-the endosymbiont evolved into mitochondria.
B)endosymbiosis of an oxygen-using photosynthetic bacterium in a larger host cell-the endosymbiont evolved into mitochondria.
C)endosymbiosis of an oxygen-using scavenger bacterium in a larger host cell-the endosymbiont evolved into lysosomes.
D)evolution of an endomembrane system and subsequent evolution of mitochondria from a portion of the Golgi.

Question

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The endosymbiotic theory proposes that mitochondria and chloroplasts evolved through the process of endosymbiosis, in which a smaller prokaryotic cell was engulfed by a larger host cell and eventually became a permanent part of it. The most likely scenario is that an oxygen-using bacterium was engulfed by a larger host cell, and over time the two cells developed a mutually beneficial relationship, with the bacterium providing energy in the form of ATP and the host supplying protection and nutrients. The endosymbiont gradually evolved into modern mitochondria, which are found in all eukaryotic cells. This theory is supported by several pieces of evidence, including the fact that mitochondria have their own DNA and ribosomes, which are similar to those found in bacteria.

The Evolution of Eukaryotic Cells Most Likely Involved