b) Assassination of Franz Ferdinand

The assassination of Archduke Franz Ferdinand of Austria in Sarajevo in 1914 was the catalyst that ignited World War I. This event set off a chain reaction of alliances and military mobilizations across Europe. The Archduke, heir to the Austro-Hungarian throne, was assassinated by Gavrilo Princip, a Bosnian Serb nationalist. The assassination highlighted the rising nationalism and ethnic tensions in the region, ultimately leading to the outbreak of one of the deadliest conflicts in human history.