I think you're not reading your text materials again, Quinn. :)
https://www.history.com/this-day-in-history/austria-hungary-declares-war-on-serbia
Which is a reason that the relationship between Austria-Hungary and Serbia dissolved?
Serbia allied with Germany, Austria-Hungary's rival
Serbia declared independence and started a revolution against Austria-Hungary
Austria-Hungary invaded northern Serbia in order to grow its empire
Austria-Hungary had annexed Bosnia and Herzegovina
Is it D?
2 answers
Is it C?