The dissolution of the Soviet Uniona occurred on 26 December 1991.
Hope this helps :D
I think the answer might be B.
Answer:
Sectionalism: Concern for one's region over concern for the entire nation.
Popular Sovereignty: the idea that people should be able to vote on important issues
States' Rights: the idea that states should hold the most political power
Nullify: to invalidate something or make it null and void.
Explanation:
Puerto Rico was acquired from the Spanish in the Spanish-American War along with Guam and the Philippines. ~Treaty of Paris~