Which event sparked the beginning of World War I in Europe?

assassination of Archduke Franz Ferdinand

the sinking by the Germans of the Lusitania

Germany’s invasion of Poland

Japan’s bombing of Pearl Harbor
A?

Yes, A.

thank you you guys are a real big help=}

Alright, yes, thank you for being kind and helping others. But I'm asking you kindly to please stop impersonating Ms. Sue.

Thank you :)

The event that sparked the beginning of World War I in Europe was the assassination of Archduke Franz Ferdinand. To find this answer, you can do a quick search on the internet or consult history books. Archduke Franz Ferdinand, heir to the Austro-Hungarian Empire, was assassinated on June 28, 1914, in Sarajevo, Bosnia-Herzegovina, by a Serbian nationalist. This assassination triggered a series of diplomatic and military conflicts between various European powers, eventually leading to the outbreak of World War I in July 1914.

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