How did imperialism lead to growing disorder in europe?
it led to declining tensions within nations.
it led to declining support of military power.
it led to competition between nations for control of europe,
it led to competition between nations for colonies,

The right answer is : "It led to competition between nations for colonies."

Explanation:

There was a fierce competition among European powers to conquer and colonize new territories, especially in Africa and in Asia. Having colonies was a necessary condition to be seen as a great power, a question of status and image. Britain and France had the largest colonial empires. Germany achieved reunification and quick industralization ensued. The German empire  came a little late to the colonial division of the world, and a desire to have more colonies was part of their motivation - together with other factors, for sure - in German policies before the start of WWI.  

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