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

Question

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?

Answer 1

Yes, A.

Answer 2

thank you you guys are a real big help=}

Answer 3

You are very welcome. :-)

Answer 4

Thank you :)

Answer 5

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