4. What are some challenges the five most populated countries might face?​

It’s either c or d as the answer.

The  franco-prussian  war, a  war  that was  led by prussia a coalition of  german  states, defeated  france. the  war  was the end  of  french  hegemony in europe and resulted in a unified  germany.  i hope this !

Answer(apex)  ok i looked up two diff, sites both say the answer is a technological innovation that has allowed people to adapt to living in hot climates, plz check first good luck///