What was Germany's greatest problem at the beginning of the war?

A. It had begun a two-front war with Russia and France.

B. A Communist revolution threatened to overthrow the Kaiser.

C. The United States had entered the war on the side of the Allies.

D. The British navy had blockaded its ports and began sinking its ships at sea.

(d) rivers.

explanation:

civilizations developed around rivers because their waters provided places to hunt and fish. also, as the rivers flooded, the lands around them became fertile. this allowed them to support farming. this is especially true of the nile river, which flooded the same time each year.

they believed democracy was worth the fight