Question

After the Archduke's assassination, all the great powers of Europe began declaring war on one another. This is

Answer 1

Answer:

B. Militarism

Explanation:

Through the process of elimination:

Alliances are based on certain powers helping each other, nationalism is a strong sense of loyalty and pride for one's nation, and imperialism is the act of conquering a land to expand an empire. :)

The concept of militarism:

Basically a strong sense that a group of people or nation should establish and maintain a strong military, which is used for the nation's interests, war, defense, and more.