You didn't list choices, but the two possible answers would be:
<h2>Germany resumed unrestricted submarine warfare.</h2><h2>The Zimmermann Telegram revealed a German attempt to gain Mexico as an ally against the United States.</h2><h2 />
Context/detail:
Public outrage in the US against the Germans swept the nation following the sinking of the British ocean liner, Lusitania, which had happened in May, 1915. When a German U-boat (submarine) sank the Lusitania, over 1,000 persons were killed, including more than 100 Americans. The passenger liner was targeted by the Germans because they suspected weapons were being shipped to Britain in the cargo hold of the ship.
Germany managed to stave off American entry into the war at the time by pledging to stop submarine attacks. But two years later, the Germans resumed such attacks. This inflamed public opinion against Germany once again and poised America to go to war.
In addition, British intelligence intercepted and decoded a telegram (known as the "Zimmermann Telegram") that showed Germany was trying to secure Mexico as an ally against the United States. The revelation of this plan inflamed feelings in the United States. The telegram was sent in January, 1917. In March, 1917, German Foreign Secretary Arthur Zimmermann admitted the telegram was, in fact, sent by his office.
In April, 1917, the US declared war on Germany in response to the Germans' submarine warfare and the Zimmermann Telegram.
The act authorized the president to grant Indian tribes unsettled western prairie land in exchange for their desirable territories within state borders (especially in the Southeast), from which the tribes would be removed.
Option C, It declared slaves to be in bondage even in free states or territories, is the right answer.
The supreme court of the United States on March 6, 1857, asserted that a Slave ( Dred Scott) who was living in the free state and territory of the United States was not allowed to his freedom and that the African -Americans were not and could never be subject of the U.S. Citizenship. Supreme Court also declared that Congress had no power to exclude slavery from the territories of U.S. This became Abolitionists (the White Northerners, who opposed Slavery) outraged from the decision made by the Supreme Court.
Food surplus gave more of the population time to develop and innovate new ideas
