Who did U. S. officials determine was behind the terrorist attacks of September 11, 2001?
O Osama bin Laden's al Qaeda network
O Saddam Hussein
O the "axis of evil"
O the Taliban and the Afghan people

Osama bin Laden's Al Qaeda network.

Explanation:

The investigation of US authorities determined that Al Qaeda, a terrorist network based in Afghanistan and other countries of the Middle East , was responsible for the 9/11 attacks. Its top leader was a Saudi man, an extremist named Osama Bin Laden, who was accused of masterminding the terrorist action on American soil. Bin Laden was killed in a commando raid by US agents in Pakistan in 2011, under the Obama administration.

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