Read the passage given below and answer the question based on it.Nationalism, aligned with imperialism, led Europe to disaster in 1914. But meanwhile, many countries in the world that had been colonized by the European powers in the nineteenth century began to oppose imperial domination. The anti-imperial movements that developed everywhere were nationalist, in the sense that they all struggled to form independent nation states, and were inspired by a sense of collective national unity, forged in confrontation with imperialism. European ideas of nationalism were nowhere replicated, for people everywhere developed their own specific variety of nationalism. But the idea that societies should be organized into 'nation-states' came to be accepted as natural and universal.Which of the following statements about 20th-century European powers is definitely true? A. They were involved in the Greek War of Independence. B. They were actively working for the unification of Germany.C. They were all working together to end the French revolution. D. They were fighting against each other in the First World War.