Answer:
c. Crime rates peaked in the 1990s and have been in sharp decline ever since.
Step-by-step explanation:
Crime rates showed their highest rates in the American history between 1970s and 1990s. Especially, violent crimes peaked in 1991. But after that crime rates in general went into a sharp decline all over the country, not only in California.
Researchers state that changes in the justice system, such as increased number of police officers and incarceration rates, are among main reasons behind this trend. Some also discuss role of as economic growth and legalized abortion. The fact that Millennials entered their prime age in the early 90s is also accounted for the decline in crime.