(A) The Spanish American War
(B) The building of the Panama Canal
(C) ** The U.S. involvement in World War I
(D) The U.S. involvement in World War II
EXPLANATIONS BELOW
Concept note-1: -The disaster immediately strained relations between Germany and the neutral United States, fueled anti-German sentiment and set off a chain of events that eventually led to the United States entering World War I.
Concept note-2: -Destroying ships not known to be carrying war materials countered accepted international war protocols. The sinking of the Lusitania heightened tensions between the U.S. and Germany and, coupled with the Zimmermann Telegram, helped sway American opinion in favor of joining the war.
Concept note-3: -This telegram, written by German Foreign Secretary Arthur Zimmermann, is a coded message sent to Mexico, proposing a military alliance against the United States.
Concept note-4: -The British luxury passenger liner RMS Lusitania was torpedoed a century ago. The sinking was deemed an atrocity of war and encouraged American intervention in World War I.