The statement which describes the alliance systems in the years leading up to World War I is ''Pre-war alliances were made in secret & elevated diplomatic tensions within those governments.''
Answer: Option B
Explanation:
One of the main reasons cause the world war 1 is the alliance system. First was between central powers like Germany, Austria-Hungary, Italy & Turkey. Second was between powers like Russia, France, Great Britain & united states.
In 1879, the secret 'dual alliance' had been formed between Germany and Austria-Hungary for assistance during the war, if Russia attack any of them. Because of this alliance system, more than 10 extra nations involved in world war 1.