Answer:
They were in between Russia and France, two of the three Triple Entente, Germany's enemies during WWI, so they were fighting a 2-front war, leading to supply line stretching.
Explanation:
The Roman Empire Split & Theodosius I made it the official religion of the Roman Empire
C Treaty of Paris______________________
A - 4
B - 2
C - 1
D - 3
i think, made the most sense at least