What Crime Led to Significant Changes in the Role of Policing

What crime led to significant changes in the role of policing in Western societies to include the collection of greater amounts of intelligence in order to better predict security threats?

A) 1988 Lockerbie bombing (Pan Am Flight 103 transatlantic flight from Frankfurt to Detroit via London and New York)
B) 2001 failed shoe bomb attempt (American Airlines Flight 63, flying from Paris to Miami)
C) terrorist attacks on New York in 2001 (commonly known as 9/11)
D) 1985 Air India Flight 182 terrorist bombing (Atlantic Ocean en route to London over Irish Airspace)