How did popular sovereignty reemerge as a definitive concept in the debates on slavery in new and existing states?

The concept of popular sovereignty implies the theory by which the citizens of a certain nation, state or city are those who have the power to decide regarding the political destinies of the territory in which they live, and that in any case the politicians, who are elected by these citizens, they must represent the will of their voters as faithfully as possible.

This concept took hold again during the debates regarding the legality of slavery in the United States in the mid-1800s, where the Democrats pushed the defense of this concept while the Whigs and later the Republicans wanted the legality of slavery to be determined by the federal Congress. Thus, in places like Kansas this situation generated confrontations between abolitionists and slavers, in the famous Bleeding Kansas.

the answer is b just took the test

the conditions that made the byzantine empire vulnerable to attacks by the muslin turks were the sack of constantinople by western crusaders, the conquests of the sultanate of rum, presence of rival kingdoms and finally the set up of fiefdoms at the empire which were owned by the ghazis (turkish warriors).