As far as none of these describe it precisely I would say A since it was a direct result of the World War I as a mean to prevent future wars and provide forum of political dispute settlement. The idea was further deveoped and evolved into United Nations once it turned out the League was not enough to stop WWII from happening.
Well the answer to your question is coming up it is just that I have to type a lot but it is C
Answer:
The 13th, 14th, and 15th Amendments, known collectively as the Civil War Amendments, were designed to ensure equality for recently emancipated slaves.
Answer:
B) introducing legislation in Congress