Question

What was the idea behind popular sovereignty in the mid-1800s
A. Allowing all Americans to vote for the president
B. Allowing newly added territories to the United States decide for themselves the slavery issue
C. Allowing newly added territories to the United States to decide for themselves their own form of government
D. Allowing slaves the rights to own property and vote

Answer 1

B. Allowing newly added territories to the United States decide for themselves the slavery issue

This was the big idea of popular sovereignty. In "border" states, voters were allowed to determine slavery, which eventually led to brawls and deaths in the streets over voting as people from across the U.S. flooded these states.

Answer 2

Hello.

The answer is 

B. Allowing newly added territories to the United States decide for themselves the slavery issue

Have a nice day