Kirby, in Her Examination of 27 Juvenile Serial Killers, Classified

Kirby, in her examination of 27 juvenile serial killers, classified offenders into three categories:

A) primary juvenile offenders, secondary juvenile offenders, and tertiary juvenile offenders
B) primary juvenile offenders, maturing juvenile offenders, and secondary juvenile offenders
C) maturing juvenile offenders, mature juvenile offenders, adult offenders
D) juvenile offenders, adult offenders, and elderly offenders