Which of these was NOT a cause of WW1? 1. European countries were building up their militaries,
2. Many European countries signed alliances.
3. There was competition among European countries to colonize new lands.
4. The Slavic people revolted against the Serbian government to have their own country

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.

why was the national assembly formed by the third estate?

the estates-general had not been assembled since 1614, and its deputies drew up long lists of grievances and called for sweeping political and social reforms. the third estate, which had the most representatives, declared itself the national assembly and took an oath to force a new constitution on the king.