Final answer:
The events in chronological order are: Assassination of Arch Duke Franz Ferdinand > U.S. remains neutral > Germany resumes Unrestricted Submarine Warfare > U.S. Declares war on Germany
Step-by-step explanation:
The events can be put in the correct chronological order as follows:
- The Assassination of the Arch Duke Franz Ferdinand. This event triggered Austria-Hungary to declare war on Serbia, which in turn triggered Russia to declare war on Austria-Hungary.
- The U.S. remains neutral and stays out of the conflict. At this time, the U.S. did not get involved in the war.
- Germany resumes Unrestricted Submarine Warfare on the U.S. In 1917, Germany announced that it would engage in unrestricted submarine warfare, which posed a threat to U.S. merchant ships.
- The U.S. Declares war on Germany and officially enters the war. The sinking of U.S. ships and the Zimmerman Telegram made a powerful argument for a declaration of war. On April 2, 1917, President Wilson asked Congress to declare war on Germany, and on April 6, the U.S. officially entered the war.