Describe the sinking of the lusitania and it's effects on american public opinion at the time

The sinking of Lusitania was a public relations nightmare for Germany as public opinion in the United States turned against them. ... In April 1917, the United States Congress voted to declare war on the Central Powers and entered World War I. The U.S. still doesn't enter the war, but is now ready.

the answer is use of support  

the graph shows the spread of railways in the 1800s.

based on the graph, the conclusion that can be drawn about germany is answer d)   by 1880, germany had more rail lines than great britain and russia.