To Apply Marx's Theory to Russia and China, Lenin and Mao

To apply Marx's theory to Russia and China, Lenin and Mao had to deal with the problem that

A) capitalism was succeeding in their countries, so people were not likely to want to overthrow it.
B) few people in their countries could read German, so few could read Marx's writings.
C) Marx had always called for gradual evolution to socialism rather than violent revolution.
D) Marx expected the revolution to begin in industrialized, capitalist societies.
E) Marx had devoted all his efforts to bringing about a revolution in his German homeland.