The correct answer to this open question is the following.
Although there are no options attached we can say the following.
Some historians write that World War I (the Great War) was avoidable. What institutions and ideas developed after 1919 to prevent a recurrence?
The most important institution developed after World War I was the League of Nations. It was created to maintain peace in the European continent and avoid another great war.
Why did they fail by 1939?
It failed mainly for two reasons, The United States decided to not be part of the League of Nations. And the other reason was that the League had no enough resources to enforce its legislation.
Originally, United States President Woodrow Wilson's goal for the League of Nations was international security and stability.
After the Allied victory in World Word II, United States President Woodrow Wilson delivered a speech before Congress in which he presented his famous "14 Point Plan." This plan aimed to find good ways to establish peace and harmony in a conflictive world after the pain and suffering left by WWII.
However, the plan was not considered during the Treaty of Paris negotiations, More than peace, what countries such as France and Great Britain wanted was revenge against Germany for the destruction caused during the war.