Correct Answer:
D. 9/11 incident
Correct answer: 9/11 incident. The September 11, 2001 attacks led the US to declare the global war on terrorism.
- Cold War: The Cold War was a decades-long rivalry with the Soviet Union.
- Missile Crisis of Cuba: The Cuban Missile Crisis took place in 1962.
- Bombing of Pearl Harbor: Pearl Harbor (1941) brought the US into the Second World War.