Final answer:
The abolitionists argued for Dred Scott's freedom on the grounds of violation of human rights.
Step-by-step explanation:
The abolitionists argued for Dred Scott's freedom primarily on the grounds of violation of human rights. They believed that as a human being, Dred Scott should not be held in bondage and that all individuals have the right to freedom and equality. The Supreme Court's decision in Dred Scott v. Sandford denied Scott his freedom and perpetuated the unjust system of slavery.
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