The most accurate response regarding the immediate impact of the first plane hitting the North Tower is:
It led to a coordinated citywide emergency response and confusion among officials.
The crash created chaos and uncertainty, prompting emergency services to respond quickly while also leading to confusion about the nature of the event, which later revealed itself to be part of a coordinated terrorist attack. This set the stage for subsequent events, including the response to the second plane hitting the South Tower and the overall crisis management required in the aftermath.