Respuesta :
Answer: by defend to serbia
Explanation:
Russia mobilised her armed forces in late July ostensibly to defend Serbia, but also to maintain her status as a Great Power, gain influence in the Balkans and deter Austria-Hungary and Germany. This led Germany to declare war on Russia on 1 August, ultimately expanding the local conflict into a world war.
Russia saw itself as the protector of all Slavs, and felt as though they needed the protect the Serbians. Helping Serbia would also increase their influence in the balkans.