According to Marx, in the Universal Struggle Between Proletarian and Bourgeois

According to Marx, in the universal struggle between proletarian and bourgeois, _____.

A) proletarians must ceaselessly press their demands for better wages and hours
B) proletarians must take control of the government through the ballot box
C) periods of industrial peace must be used by proletarians to focus on political goals
D) proletarians who try to improve their economic conditions betray their class interest