How did other european nations respond to german imperialism and militarism before world war i?

they ignored germany's militarism and imperialism in an effort to avoid war.
they launched massive attacks on germany's naval fleet to limit its naval force.
they built up their supply of arms and made agreements to support each other in the event of war.
they focused on nationalist movements in their own nations and rejected military alliances with others.

They built up their supply of arms and made agreements to support each other in the event of war.

Explanation:

One of the reasons why World War I was able to reach such an enormous scale was because many of these countries had made previous alliances, which meant that they had committed themselves to supporting each other in the event of a war. The war had seemed likely for a while, as German imperialism was on the rise and it threatened the borders of Europe. More importantly, it threatened the balance of power, an important concern for the continent. This lead them to build up their supply of arms.

the correct answer is

d) rocket launcher