Respuesta :
The role played by German leaders in the Austria-Hungary decision on Serbia was A. They promised to support Austria-Hungary after it threatened to invade Serbia.
How did Germany support Austria?
When Austria wanted to declare war on Serbia, they were worried about Russia protecting Serbia and so they sought help from Germany.
Germany promised to support Austria-Hungary if they decided to declare war which led to the Austrians doing just that.
Find out more on Germany and Austria-Hungary at https://brainly.com/question/14829155.
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