For Europe, What Was the Most Striking and Long-Term Impact

For Europe, what was the most striking and long-term impact of the outcome of the Franco-Prussian War?

A) The amazing and immediate rise of influence in Europe by the United States.
B) The unification of the many independent sections of Germany into a country.
C) The French accepted German domination for the rest of modern history.
D) The English exploited the war between France and Germany to seize French territory.
E) The Russians were able to enact their reforms while the other countries were at war.