(A) use of poison gas
(B) Schlieffen Plan
(C) ** submarine warfare
(D) secret agreement
EXPLANATIONS BELOW
Concept note-1: -Wilson cited Germany’s violation of its pledge to suspend unrestricted submarine warfare in the North Atlantic and the Mediterranean, and its attempts to entice Mexico into an alliance against the United States, as his reasons for declaring war.
Concept note-2: -The main reason for the American entry into World War I was the German use of submarine warfare (1917), violating the United State right to freedom of the seas. German was suffering from near-starvation due to a lack of supplies and food.
Concept note-3: -He served two terms in office, from 1913 to 1921. Wilson was a Progressive Democrat who believed in the power of the federal government to expose corruption, regulate the economy, eliminate unethical business practices, and improve the general condition of society.
Concept note-4: -Wilson informed Congress of an ultimatum sent to the German government a day earlier, in which he condemned Germany’s policy of unrestricted submarine warfare, which resulted in merchant vessels being sunk without warning should they be suspected of trading with the Allies.
Concept note-5: -Wilson thought that the United States alone could shape an effective peace settlement because he believed that the combatants were politically and morally bankrupt. Wilson felt that American intervention in 1917 would ensure that the United States would play a decisive role and dominate the postwar peace conference.