Final answer:
Al Qaeda was responsible for the 9/11 attacks, which were coordinated and carried out by the terrorist group.
Step-by-step explanation:
Al Qaeda was responsible for the attacks during 9/11/2001. This terrorist group, founded by Osama bin Laden, carried out the coordinated attacks on the World Trade Center and the Pentagon. The attacks resulted in the deaths of nearly 3,000 people.
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