Question

al-qaedas main targets on september 11, 2001, were
boston, pennsylvania, and new york city.
pennsylvania and washington, dc.
new york city and washington, dc.
boston, new york city, and washington, dc.

Explanation:

On September 11, 2001, Al-Qaeda targeted the World Trade Center in New York City, the Pentagon in Washington, DC. The plane that crashed in Pennsylvania was believed to be heading to a target in Washington, DC, but the primary intended main targets were New York City and Washington, DC.

Answer:

New York City and Washington, DC.