(A) ** Central Powers
(B) Allies
(C) Triple Entente
(D) Triple Alliance
EXPLANATIONS BELOW
Concept note-1: -The Central Powers, also known as the Central Empires, was one of the two main coalitions that fought in World War I (1914–1918). It consisted of the German Empire, Austria-Hungary, the Ottoman Empire, and the Kingdom of Bulgaria and was also known as the Quadruple Alliance.
Concept note-2: -The Allies described the wartime military alliance of Germany, Austria-Hungary, Bulgaria and the Ottoman Empire as the ‘Central Powers’. The name referred to the geographical location of the two original members of the alliance, Germany and Austria-Hungary, in central Europe.
Concept note-3: -The Allies of World War I, Entente Powers, or Allied Powers were a coalition of countries led by the United Kingdom, France, Russia, Italy, Japan, and the United States against the Central Powers of Germany, Austria-Hungary, the Ottoman Empire, Bulgaria, and their colonies during the First World War (1914–1918).
Concept note-4: -Central Powers, World War I coalition that consisted primarily of the German Empire and Austria-Hungary, the “central” European states that were at war from August 1914 against France and Britain on the Western Front and against Russia on the Eastern Front.
Concept note-5: -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.