Biologist lynn margulis proposed a theory stating that different prokaryotic organisms joined in symbiosis to eventually become eukaryotic cells. which statement supports her theory?

a mitochondria do not use oxygen to produce energy.
b mitochondria have their own dna different from the chromosomal dna in the nucleus.
c smaller eukaryotes were swallowed by larger ones and became organelles within the larger ones.
d large prokaryotes swallowed small eukaryotes and became the organelles for the new larger eukaryotes.