(A) Nationalism
(B) ** Militarism
(C) Alliances
(D) Imperialism
EXPLANATIONS BELOW
Concept note-1: -Militarism denoted a rise in military expenditure, an increase in military and naval forces, more influence of the military men upon the policies of the civilian government, and a preference for force as a solution to problems. Militarism was one of the main causes of the First World War.
Concept note-2: -This increase in militarism helped push the countries involved into war. The immediate cause of World War I that made the aforementioned items come into play (alliances, imperialism, militarism, nationalism) was the assassination of Archduke Franz Ferdinand of Austria-Hungary.
Concept note-3: -noun. Britannica Dictionary definition of MILITARISM. [noncount] : the opinions or actions of people who believe that a country should use military methods, forces, etc., to gain power and to achieve its goals. The administration has been criticized for the militarism of its foreign policy.
Concept note-4: -Definition: Militarism is a belief in building up the nation’s military forces as the best way to increase the nation’s power and prestige in the world. Even before the war began in 1914, many countries in Europe had been expanding their armies and navies.