Why was Archduke Franz Ferdinand of Austria-Hungary a key player in World War I? He ordered an attack on Serbia.
He was assassinated by a Serbian nationalist.
He created an alliance with Great Britain.
He authorized the use of poison gas on Russia.

He was assassinated by a Serbian nationalist.

Explanation:

Archduke Franz Ferdinand of Austria-Hungary was an instrumental key figure in World War 1 because it was his assassination in Sarajevo on June 28, 1914 by a Serbian nationalist that caused the declaration of war between Austria and Serbia.

Until his death, he was heir to the throne in Austria.

c  

explanation:

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