(A) rebellions in colonial lands in Africa and Asia
(B) expansion of communism into western Europe
(C) ** militarism in the nations of Europe
(D) inability of the League of Nations to keep the peace
EXPLANATIONS BELOW
Concept note-1: -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: -Great Britain and Germany both greatly increased their navies in this time period. Further, in Germany and Russia particularly, the military establishment began to have a greater influence on public policy. This increase in militarism helped push the countries involved into war.
Concept note-3: -Causes of World War I. It is widely believed that the assassination of Archduke Franz Ferdinand and his wife during a visit to Serbia is the spark that ignited the conflict of World War I.
Concept note-4: -What was the main cause of World War I? World War I began after the assassination of Austrian archduke Franz Ferdinand by South Slav nationalist Gavrilo Princip on June 28, 1914.