Which best explains why the abolitionist movement grew stronger as result of the Scott v. Sandford ruling?

The North realized that if it did not act swiftly, the Southern states might take the precedent of the Scott case as a justification for expanding slavery into new territories and free states alike. The South recognized the threat of the Republican party and knew that the party had gained a considerable amount of support as a result of the Northern paranoia in the aftermath of the decision.