(A) Militarism
(B) Alliances
(C) ** Imperialism
(D) Nationalism
EXPLANATIONS BELOW
Concept note-1: -European Expansionism The expansion of European nations as empires (also known as imperialism) can be seen as a key cause of World War I, because as countries like Britain and France expanded their empires, it resulted in increased tensions among European countries.
Concept note-2: -How did Imperialism cause WWI? Nations competed for more land, colonies and raw materials. Great Britain and Germany competed industrially, which led to these nations needing more raw materials. Also, Austria-Hungary controlling the Slavic land of Bosnia, which Serbia believed belonged to them.
Concept note-3: -Imperial rivalry and competition for new territories and possessions fuelled tension between major European nations and became a factor in the outbreak of war.
Concept note-4: -Western European empires like Great Britain and France had overseas colonies around the world, while eastern empires like Austria-Hungary and Russia ruled European and North Asian territories connected by land.