(A) 1918
(B) 1917
(C) 1915
(D) ** 1914
EXPLANATIONS BELOW
Concept note-1: -Austria-Hungary declares war on Serbia, beginning World War I.
Concept note-2: -World War I began after the assassination of Austrian archduke Franz Ferdinand by South Slav nationalist Gavrilo Princip on June 28, 1914. Read more about why the Balkans became the “powder keg of Europe.”
Concept note-3: -The assassination of Austrian Archduke Franz Ferdinand (June 28, 1914) was the main catalyst for the start of the Great War (World War I).
Concept note-4: -This year saw the beginning of what became known as World War I, after Archduke Franz Ferdinand of Austria, heir to the Austrian throne was assassinated by Serbian nationalist Gavrilo Princip.
Concept note-5: -Austria-Hungary, with German encouragement, declared war on Serbia on 28 July. Russia’s support of Serbia brought France into the conflict. Germany declared war on Russia on 1 August and France on 3 August.