Answer:
The immediate cause of World War I that made the aforementioned items come into play (alliances, imperialism, militarism, nationalism) was the assassination of Archduke Franz Ferdinand of Austria-Hungary. In June 1914, a Serbian-nationalist terrorist group called the Black Hand sent groups to assassinate the Archduke.
Explanation:
Answer: Assassination
Explanation: The assassination of Archduke Franz Ferdinand of Austria-Hungary by a Serbian-nationalist terrorist group called the Black Hand sent groups to assassinate him in the month of June 1914.
