I believe the answer here would be C. but I'm not 100% sure so don't quote me on it.
A major cause of the Russian Revolution of 1917 was the C. existence of sharp economic differences between social classes.
D) the United States and the Soviet Union
archduke Franz Ferdinand got assassinated, and all his allies attacked the country where the assassins were from, and then all of those countries allies attacked the allies of the countries attacking their ally, and then there was trench warfare in Europe, first tanks came around, poison gas was used and was very deadly, and in the end Germany got their butt kicked
Andes mountains is one of the features
