B, because the communists believed that there would be a revolution from the working people. They would stand up agains the higher classes and then there would be a situation in which the proletariat would have the power and eventually, the society would change in one without classess.
And socialists didn't want to be so violent and tried to get similar results in a 'normal' way.
Poor living conditions
Cubans revolted many times under Spanish rule
Us stepped in in 1898 which led to the Spanish American war Cubans gained freedom