The three events that contributed to President Woodrow Wilson's decision to ask for a declaration of war against Germany were:
A. Germany's violation of its pledge to suspend unrestricted submarine warfare.
C. Germany's attempt to engage Mexico into an alliance against the United States.
D. The sinking of the ocean liner Lusitania.
These events significantly heightened tensions between the United States and Germany and played crucial roles in shaping public opinion and government policy leading up to the U.S. entry into World War I.