The Mitochondria in many cells, are believed to have been bacteria that have been incorporated in the cytophysiology. Mitochondria first off, contain their own DNA, er, RNA. Additionally physiologically the mitochondrion, has an inner membrane and some organelle traits similar to prokaryotic cells. Lastly Mitochondria are the only organelle capable of replicating itself. <span />
I believe the answer is B. Hope I help! Sorry if not. ):)
No our galaxy does not contain any planets outside our solar system
