Who was the President of the United States during World War I?

Woodrow Wilson served as the President of the United States during World War I, which lasted from 1914 to 1918, but the U.S. entered the war in 1917. Wilson's leadership during this time was significant, as he initially advocated for neutrality but later pushed for American involvement when it became clear that the conflict would affect U.S. interests. His administration is also noted for its efforts in promoting the League of Nations, an organization aimed at ensuring peace and preventing future conflicts, reflecting his vision for a post-war world.

The other individuals listed were not presidents during the war. Theodore Roosevelt served from 1901 to 1909, Herbert Hoover's presidency began in 1929, and Franklin D. Roosevelt took office in 1933, years after the conclusion of World War I. Thus, Wilson is the only correct answer as he was directly involved in leading the country through this pivotal period in history.