The main idea of the quotation is that a small group of wealthy people thrive thanks to the toil of the working classes.
This leads to a great gap between the classes: the millionares, who reap the work of others and create injustice, and the poor who are not paid their dues.
"B. the decline of monarchies" was not a remote cause of the outbreak of World War I, since many of the European countries that entered the war still had kings and queens.
