It was first introduced in Woodrow Wilson's Fourteen points ( A )
It was outlined in Article X of the Treaty of Versailles ( D )
Explanation:
The league of nations is a intergovernmental organization established for the sake of world peace which was founded/pioneered by Woodrow Wilson. the league of Nations was established on 10th January 1920 after the peace conference that took place in Paris which helped to end world war 1. In this peace conference the treaty of Versailles was drafted and helped to promote peace.
One of the items outlined in this treaty was the league of Nations which was outlined in Article X of the Treaty of Versailles. Woodrow Wilson the pioneer of the League of Nations was the president of the United states of America.
The main purpose of the League was to prevent war by collective security and collective disarming any Nation trying to cause War.
