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.
