Answer:
The correct answer is 3. Endosymbiotes
Explanation:
According to the endosymbiotic theory, mitochondria was a prokaryotic organelle which was engulfed by ancestral cell. Then this bacteria remain in a symbiotic relationship with ancestral cell and evolved in mitochondria which can synthesize ATP and replicated its own genome, able to duplicate and divide.
So mitochondria are considered as endosymbiotes which means they are organism which lives inside others body and cannot live or function on their own. This theory is supported by genetic evidence that shows similarities between mitochondria and bacteria. So the correct answer is 3.