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.
The correct answers should be A. Bombing more than 60 Japanese cities, C. Declaring a Soviet attack on Japan, and E. Issuing the Potsdam Declaration
The bombing of the cities is often overlooked because of the big two bombs and not many people talk about this. Soviets were preparing to invade occupied pieces of China and free it, as well as attack Hokkaido as it was their deal with allies. The Potsdam declaration was made by the allies in which they requested capitulation of Japan with complete destruction being offered if the declaration was not accepted.