Answer:
B: it was the first attempt to create an organization where nations working together for peace
Step-by-step explanation:
Why it's not A: If the League of Nations was an effective tool (in which it had military and political power), then World War II would never have happened.
Why it's not C: Many nations within the League of Nations could not agree on the terms and conditions for everything inside the treaty. This also helped build the foundation in which World War II was based off of.
Why it's not D: The United States returned back to her policy of isolation. The United States was not seen as a major world power until World War II, and before then it was seen mostly as a regional power.
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