The reason that president Wilson gave for the Congress to support his request for a declaration of war was (b.) that the german agenda threatened democracy.
The United States officially entered World War I in April 1917. The U.S. president during the entire war was Woodrow Wilson. He was the one that requested the Congress to support his declaration of war since he believed that democracy had to be protected. Wilson had already broken off diplomatic relations with Germany but Germany, which had an unrestricted submarine warfare, tried to convince Mexico to go to war against the United States in exchange of financial and territorial rewards; in other words, Germany would help Mexico to regain Texas, New Mexico and Arizona if they fought against the United States. Wilson felt that the country could not stand that and decided to fight for the rights and liberties of the United States by declaring war. Consequently, the House of Representatives voted in favor of the war by 373 votes to 50.