The Zimmerman telegraph, was a telegraph from Germany to Mexico proposing an alliance in which Germany would give the land that Mexico lost to the United States if the Mexican people would fight the United States and keep them out of the war
There are more than three reasons why this happened of course but the best three are there they needed more land, resources, and some way to escape the cold.
D is correct answer.
Sword Excalibur it was forged by Merlin.
Hope it helped you.
-Charlie