I need help with 13 a and b please

What element does susan b. anthony include in this passage to strengthen her argument?

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

Penelope studies how the structure and function of the nervous system is related to behavior. she is a psychologist