(A) ** World War I
(B) The Franco-Prussian War
(C) World War II
(D) The Russo-Japanese War
EXPLANATIONS BELOW
Concept note-1: -The assassination of Archduke Franz Ferdinand, heir to the Austro-Hungarian throne, and his wife Sophie in Sarajevo (the capital of the Austro-Hungarian province of Bosnia-Herzegovina) on 28 June 1914 eventually led to the outbreak of the First World War.
Concept note-2: -The assassination set off a rapid chain of events, as Austria-Hungary immediately blamed the Serbian government for the attack. As large and powerful Russia supported Serbia, Austria asked for assurances that Germany would step in on its side against Russia and its allies, including France and possibly Great Britain.
Concept note-3: -The assassination of Archduke Franz Ferdinand was the immediate cause of a war between two great powers-Russia and the Habsburg Austro-Hungarian Empire.
Concept note-4: -The assassination of the Austrian Archduke Franz Ferdinand in 1914 was the immediate cause of the First World War. For four years, the great European powers fought a gruesome battle. Gavrilo Princip is arrested.