Answer:
b
Step-by-step explanation:
you see the European powers never liked when one place got too much power and would unite to stop them (for example napoleon or the wars of the spansih succession) later they formed treaties with each other as a deterent. a great example of this is ww1 Europe erupted in war and if there had been no treaties it would have been a war between Serbia and Austria hungry. so that is why the answer is b