The effect of the use of parallel structure in the sentence in bold as It emphasizes that the victims of the 9/11 attacks were everyday people.
Option D is correct
On the morning of 11 September 2001, 19 Al Qaeda terrorists hijacked four commercial passenger planes within the United States.
Two planes were flown into the dual Towers of the World Trade Center in New York City, causing both towers to collapse. A 3rd plane was crashed into the Pentagon, just outside Washington, DC. The 4th plane crashed in a rural Pennsylvania after the crew members and passengers attacked the terrorists on board, preventing it from hitting another target thought to be the White House.
September 11, 2001 Commemoration
The 9/11 terrorist attacks killed 2,977 people and this injured thousands of people at the World Trade Center, the Pentagon, and in the Somerset County, Pennsylvania.
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