7. What event directly led to World War I?

A. the killing of Archduke Francis Ferdinand

B. explosion of the battleship Maine

C. German concentration camps

D. bombing of Pearl Harbor

A. the killing of Archduke Francis Ferdinand

The correct answer is A. the killing of Archduke Francis Ferdinand. The assassination of Archduke Francis Ferdinand, the heir to the Austro-Hungarian throne, by a Serbian nationalist in June 1914, directly led to the outbreak of World War I. This event triggered a series of diplomatic tensions and military actions between various countries, eventually escalating into a global conflict.