Many factors changed american opinion of the great war and eventually led to a us declaration of war in germany, which of the following was not one of these factors?

What are the factors shown?  I know the sinking of the Lusitania and the Zimmerman telegram were two major factors.

The massacre of thousands of Armenians by the German army

Explanation:

The Massacre of Armenians by the German army did not influence public opinion on Germany. Instead, other factors influenced public opinion such as the atrocities that the German Army did against civilians in Belgium, the use of unrestricted submarine warfare by Germany that eventually killed many Americans that were on board on British ships such as the Lusitania.