How did the annexation of Bosnia and Herzegovina in 1908 intensify the rivalry between Austria-Hungary and Serbia?

Austria-Hungary annexed Bosnia and Herzegovina in 1908, angering Serbia, which wanted to unite South Slavic peoples and had hoped to expand its influence there. Serbia vowed to reclaim the territory from Austria-Hungary, increasing tensions between the two countries. The correct choice is “Serbia vowed to take back the annexed territory from Austria-Hungary.”

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