The leader of the Afghan terrorist group, al-Qaeda, who was believed to have masterminded the 9/11 attacks and was later assassinated by the US, is Osama bin Laden. Here's why:
1. Osama bin Laden was the founder of the militant Islamist organization al-Qaeda, which was responsible for the 9/11 attacks on September 11, 2001, in the United States.
2. He was considered the mastermind behind the planning and execution of the 9/11 terrorist attacks on the World Trade Center in New York City and the Pentagon in Washington, D.C.
3. Following the attacks, the United States conducted a manhunt for Osama bin Laden, who was eventually located and killed by US Navy SEALs during a raid on his compound in Abbottabad, Pakistan, on May 2, 2011.
4. The other options provided in the question, Mohammed Reza Pahlavi, Ayatollah Ruholla Khomeini, and Saddam Hussein, were not associated with leading al-Qaeda or being responsible for the 9/11 attacks.
