"Crackdowns" Are Sudden Changes in Police Activity Designed to Lower

"Crackdowns" are sudden changes in police activity designed to lower crime rates through an increase in the communicated threat or actual certainty of punishment. What does research indicate about the effectiveness of crackdowns?

A) Merely saturating an area with police deters crime.
B) Crackdowns initially deter crime, but the effect soon wears off after the high-intensity police activity ends.
C) Crackdowns are ineffective when coupled with aggressive problem-solving and community-improvement techniques.
D) Crackdowns initially do not work but later lead to a long-term decrease in crime