(A) ** 1914
(B) 1917
(C) 1918
(D) 1919
EXPLANATIONS BELOW
Concept note-1: -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-2: -The assassination of Austrian Archduke Franz Ferdinand (June 28, 1914) was the main catalyst for the start of the Great War (World War I). After the assassination, the following series of events took place: July 28-Austria declared war on Serbia.
Concept note-3: -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-4: -Over 30 nations declared war between 1914 and 1918. The majority joined on the side of the Allies, including Serbia, Russia, France, Britain, Italy and the United States. They were opposed by Germany, Austria-Hungary, Bulgaria and the Ottoman Empire, who together formed the Central Powers.