What role did nationalism play in the outbreak of world war i?           a. nationalism convinced the people of europe that their own nation could take on any military threat.   b. nationalism led to a new era of peace negotiations.   c. nationalism caused a reduction in trade.   d. nationalism caused countries to stop the alliance system.  

Your answer is A Nationalism convinced the people of Europe that their own nation could take on any military threat because although they were not directly influence by nationalism they needed to let Europe know that they got a lot of man power and insisted that they are more powerful than any other military threat also it is not because it never went in negations about peace its also not C because trade was everything hack then to make money if they loss trade they won't make money they won't get homes and loss their homes to tax's and when it came down to rather A, and D I choose A because D nationalism is all about coming togther its not about breaking alliances with other countries around the world.

Your answer is A.

The answer is crop yield.