Why did a conflict develop between Serbia and Austria-Hungary in the years leading up to World War I?
A. Serbians believed that Austro-Hungarian lands with large Serb
populations should join Serbia,
B. Austro-Hungarians began a campaign of genocide against Serbs
in their territory
O C. Serbian military forces joined the Ottoman Empire in its attacks
against Austria-Hungary.
D. Austro-Hungarian nationalists assassinated the leader of Serbia's
ruling political party.