Question: On what day of which month were the two buildings in Lower Manhattan, developed by the American businessman Larry Silverstein, destroyed?
Sentence (from "World Trade Center (1973–2001)"): At the time of their completion, the "Twin Towers"—the original 1 World Trade Center, at 1368 ft ; and 2 World Trade Center, at 1,362 ft —were the tallest buildings in the world.
Relevant evidence: No