A. World War I
B. World War II
C. The Korean War
D. The Vietnam War
Answer: World War I
A. World War I
B. World War II
C. The Korean War
D. The Vietnam War
Answer: World War I
Additional Information: The assassination of Archduke Franz Ferdinand in 1914 is widely recognized as the catalyst for the outbreak of World War I.
Subjects: World History, General Knowledge