The correct response to complete the sentences is "Dred Scott decision." Here's how the completed sentences would read:
"The Dred Scott decision was a Supreme Court case that angered the North because it stated that enslaved people were not citizens and were considered property. In addition, it meant that the Missouri Compromise was unconstitutional."
If "Missouri Compromise" is one of your options, use that to fill in the second response area. If you have other options, please provide them for further assistance!