Answer:
The common thread putting the three events together is the issue of slavery, the most polemic issue of the pre-war era, the one that ignited the strongest passions in the decades previous to the Civil War. The compromise of 1850 relates to the status of new states admitted after the Mexican-American War; the Dred Scott decision is a Supreme Court sentence; and the Kansas-Nebraska Act is a fiercely disputed piece of legislation.
Explanation:
