Question

which of the following ethnic groups wanted to break from Austrian control before World War 1

Answer 1

Is one of your choices...Serbs? If so, I believe that is the answer.
Hope this helps!

Answer 2

Page 562 of the book

Austria-Hungary also confronted nationalism within its realms, especially the aspirations of Slavic peoples—Poles, Czechs, Slovaks, Serbs, Croats, and Slovenes.

Answers: Serbs