Criminologists Often Encounter Difficulties When They Attempt to Evaluate Programs

Criminologists often encounter difficulties when they attempt to evaluate programs or policies using a randomized experimental model with control and treatment groups. Agnew and Brezina illustrate such difficulties with which of the following examples?

A) Juvenile court personnel violate the random assignment procedure.
B) Juveniles select the treatment group over the control group.
C) Researchers lack adequate funding.
D) Researchers lose interest in the study before it is completed.
E) all of the above