Answer: C. The Supreme Court’s decision benefited the slave owners and said that slaves were not citizens
Explanation:
Dred Scott v. Sandford (1856) was a Supreme court case whereby the court decided that blacks shouldn't be given American citizenship and the constitutional rights that are enjoyed by American citizens doesn't apply to them.
The court ruled that slaves were just properties of their owners and that they shouldn't become citizens. Therefore, the Supreme Court’s decision benefited the slave owners.