HELP PLEASE
How did the German use of U-boats and “unrestricted submarine warfare” affect American opinion of Germany?

Select one:
a. Because passenger liners and other non military vessels were attacked by U-Boats, many Americans turned their opinions against Germany.
b. Most Americans felt that Germany was within its rights since it was only attacking military ships.
c. Most Americans supported Germany during the early years of the war because they admired their strong navy.
d. The German U-Boats had very little effect on U.S. opinion.