Archduke Franz Ferdinand was pivotal in supporting Austria-Hungary's ambitions in the Balkans, fueling tensions with Serbia and other nations. His assassination ultimately led to the outbreak of World War I, highlighting the fragile power dynamics of the era. The conflict represented the struggle between empires and nationalist movements, particularly in the Balkans. ;
Archduke Franz Ferdinand supported Austria-Hungary's ambitions primarily in the Balkan region, where nationalist tensions were rising. His assassination in 1914 triggered World War I, showcasing the fragile power dynamics of the time. Therefore, the best choice is 'B. Balkan'.
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