Which of the Following May Be a Concern If We

Multiple Choice

Which of the following may be a concern if we are interested in studying "career drug dealers" and we use our friend from the probation department to act as our informant into that subculture?

A) those getting probation may be first time offenders
B) those getting probation have obviously been caught, and thus will not reflect those that have more skill and have not been apprehended
C) there may be some drug dealers who enter into plea negotiations and plead to possession instead of dealing
D) all of the above