Prior to the civil war, many people thought the issue of slavery should be based on popular sovereignty, which meant that a. states with large populations would be allowed to permit slavery. b. slavery would not be allowed in any state north of the state of missouri. c. the people in a territory would vote to make slavery legal or illegal. d. members of congress would vote on which states would allow slavery.

 C. The people in a territory would vote to make slavery legal or illegal.

Explanation:

"Popular" means a vote by the populace, the people.

"Sovereignty" refers to where power or authority lies.

So "popular sovereignty" means that the people of the states (or territories becoming states) had authority over their own territory's approach to the slavery issue.

The Civil War was fought over both the issue of "states' rights" (the idea of each state's popular sovereignty), as well as the issue of slavery, which was ended in the United States after the Civil War.   From that point on, at least on the issue of slavery, states could not decide their own path.  The 13th Amendment was added to the US Constitution and made slavery illegal in all states.

Here's what the 13th Amendment said:

s the president shall be commander in chief of the army and navy of the united states, and of the militia of the several states, when called into the actual service of the united states; he may require the opinion, in writing, of the principal officer in each of the executive departments. sooo yeahhh

explanation: