Answer:
The correct answer is option d. To prevent another global war by resolving conflicts with diplomacy.
Step-by-step explanation:
The League of Nations was founded in 1920. After the First World War was over the nations around the world were worried about the emergence of other global conflicts resembling the Great War.
So, in the Paris Peace Conference that took place in 1919 in which was debated the terms of the defeat of Germany and the situation of the countries, the former President of United States, Woodrow Wilson, presented fourteen principles to keep peace in the World.
Those are consider as the foundation of the League of Nations, that was stablished in 1919 with the main purpose of maintaining world peace, in which the core of the organization was resolving conflicts with diplomacy and conciliation. This is why the option D is the correct answer, for the League was urged to make a war impossible and they had understood that the origins of the Great War had had a lack of diplomacy to handle the conflict among nations.
This was supposed to bring countries together in one aim, as mentioned in option e, but this is more a prerequisite than a main purpose of the League.
The option f was also important, but still not the main purpose, because the world's economy was a concern of all the countries, for the Great War left an enormous debt, and also economy started to drop. This is why the League worried to create an international cooperation to prevent the complete drop of the world's economy.
The League as a prevention of another war to happen, there was a need to work as the ruler that sets limits and punishments to countries so they would not feel attracted to start one another. But in case of one war to happen again, they would serve as a court of justice and try war criminals, as mentioned in options A and B, respectively. This was a discussed topic and a work of the League but not the main purpose, for they were settled to avoid wars in the first place. In the same intention, the League considered to provide aid to war victims and countries ravaged by war, as mentioned in option c, as for the rebuild of the countries affected for war it becomes fundamental to supply all the help they would need.