Final answer:
The cause of World War 1, due to European nations making agreements and treaties was Alliances.
Step-by-step explanation:
The cause of World War 1 due to European nations making agreements and treaties was Alliances. These alliances were formed between countries to protect themselves or to provide support in the event of a conflict. For example, the Triple Entente consisted of France, Russia, and the United Kingdom forming an alliance to counter the threat from the Triple Alliance composed of Germany, Austria-Hungary, and Italy.
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