Answer:
The correct answer is C. The Supreme Court decision that overturned both the Missouri Compromise and popular sovereignty.
Explanation:
Dred Scott v. Sandford was a ruling of the United States Supreme Court in 1857, depriving African Americans of federal legal capacity and allowing slavery in the federal territories. The Missouri Compromise was declared unconstitutional.
Dred Scott, an African American slave had by his owner, John F.A. Sanford, taken to the Minnesota Territory where Congress banned slavery. He therefore sued him and demanded his freedom. In the lower courts he had been right, but the Supreme Court dismissed his case.
The ruling, which had been written by Supreme Court President Roger B. Taney, stated that African Americans could not be US citizens and therefore lacked federal legal capacity. The Court also found that the United States Congress did not have constitutional powers to regulate slavery in the federal territories. It was then only the second time that the court declared a federal statute unconstitutional.