What specific event in Sarajevo in 1914 is widely regarded as the immediate catalyst for the outbreak of World War I?

💡 Explanation:

The assassination of Archduke Franz Ferdinand of Austria, heir to the Austro-Hungarian throne, and his wife Sophie by a Serbian nationalist in Sarajevo on June 28, 1914, is widely considered the immediate trigger that set off a chain of events leading to the start of World War I.