4. Read the following slogans taken from posters that advertised liberty bonds in 1917 and answer the question below. Source: Lbrary of Congress Make The World Safe For Democracy Which action contributed to the need for the U.S. government to use these slogans? Swat Out Military Autocracy Every Liberty Bond You Buy Helps Win The War a trade embargo Imposed by Great Britain the sinking of passenger ships by German submarines the refusal of the United States to Join the League of Nations D. O a change In Russian leadership during the Bolshevik Revolution