Dred Scott announced that enslaved people were nationals of the U.S. is the Dred Scott v. Sanford decision assist to change state, the Civil War.
From 1846 to 1857 The Dred Scott Case in Missouri. The United States Supreme Court stunned the nation in 1857.
When it upheld slavery in US territories, denied black citizenship in America, and declared the Missouri Compromise unconstitutional.
Thus, option A is correct.
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