What best summarizes why part of the nation was upset over the Fred Scott decision?

The Dred Scott decision, delivered by the Supreme Court in 1857, ruled that enslaved individuals were not citizens and therefore had no standing to sue in federal court. This ruling infuriated many in the Northern states, as it effectively denied the possibility of citizenship for African Americans and reinforced the institution of slavery. Additionally, it invalidated the Missouri Compromise, which had attempted to limit the spread of slavery in the territories, further escalating tensions between pro-slavery and anti-slavery factions and contributing to the national divide leading up to the Civil War.