(A) The Axis & The Allies
(B) ** The Triple Alliance & The Triple Entente
(C) The West & The East
(D) Oceania & Eurasia
EXPLANATIONS BELOW
Concept note-1: -The Triple Entente was made up of France, Britain, and Russia. The Triple Alliance was originally composed of Germany, Austria–Hungary, and Italy, but Italy remained neutral in 1914.
Concept note-2: -World War I had two main factions: the Central Powers, which included Germany, Austria-Hungary, Bulgaria and the Ottoman Empire; and the Allies, which included France, Great Britain, Russia, Italy, Japan and later, the United States.
Concept note-3: -Triple Alliance, secret agreement between Germany, Austria-Hungary, and Italy formed in May 1882 and renewed periodically until World War I. Germany and Austria-Hungary had been closely allied since 1879. Italy sought their support against France shortly after losing North African ambitions to the French.
Concept note-4: -Each nation pledged to fight if any of its allies were attacked. One alliance included Germany, Austria-Hungary and Italy, called the Triple Alliance. Opposing them was the Triple Entente of France, Russia and England.
Concept note-5: -The Triple Entente (from French entente [ɑ̃tɑ̃t] meaning “friendship, understanding, agreement") describes the informal understanding between the Russian Empire, the French Third Republic, and the United Kingdom of Great Britain and Ireland as well as Romania, which joined later.