The river Nile left behind rich soil when it flooded. So the correct option for the given question is option "B". The river Nile brought with it very rich soil from other places and deposited them in the flood plains. when the flood water receded, the farmers were able to cultivate the land and get a rich vein of crops for feeding all the people making up the civilization near the river banks of Nile. Every year, with new flooding of the plains, new rich soil is brought abd deposited. The farmers are able to reap great crops in the flood plains of the river Nile every year due to this reason.
Germany, Austria-Hungary, Turkey, Ottoman empire and Bulgaria were the central powers. These were also known as the quadruple alliance.
I think it D.
i hope this helped!
North Korea is in the continent of Asia.