Is endosymbiothic a feasible theory, does it have enough evidence to be reliable?

Question

Is endosymbiothic a feasible theory, does it have enough evidence to be reliable?

Answer 1

Despite this being the Physics section, I do agree with the Endosymbiotic theory, as it explains a lot of the discrepancies found in certain organelles. For me, the main fact behind this theory is mitochondrial DNA, which is different from the cell hosting it.

And it does seem a rather logical theory.