The events of september 11, 2001, were heavily financed by: the saudi government osama bin laden saddam hussein khalid sheikh mohammed

The events of September 11, 2001 were heavily financed by Osama bin Laden as he was the head of the terroristic organization known as Al Quaeda, an importnat terroristic organization known at the time. He also took responsibility for the attacks later on. 

The answer b is correct this all occurred during the red scare