Can someone help me with this plz

What did not occur in the proterozoic eon a)the oxygen levels increase greatly in the atmosphere,b)the emergence of the eukarya , c)muti cella’s eukaryotic organisms began to diversify,d)anaerobic bacteria kept thriving with more oxygen

Will mark you as ! keiko’s teacher was discussing the theory of endosymbiosis. she asked keiko to mark the organelles in the diagram that most closely resembled prokaryotes. which organelles should keiko mark? * the first image is the question and the second image is some information to you answer the !

Which is a function performed by stem cells in the skin a. replacing lost skin cells b. making cells for the intestines c. growing new organs d. differentiating into brain cells plz apex