Answer:
Correct answer is 4. The Slavic people revolted against the Serbian government to have their own country
Explanation:
Option four is correct as South Slavs wanted to create a country, in which Serbia would be also included. After the war ended this country was actually created - Kingdom of Serbs, Croats and Slovenians.
First option is not correct as all European forces were militarized and nationalized.
Second option is not correct as great alliances, such as Entente and Central Powers were created.
Third option is not correct as Germany first of all wanted more colonies.
