One Explanation for the Disproportionate Number of Mentally Ill People

One explanation for the disproportionate number of mentally ill people in jail and prison is that many

A) were mistakenly categorized as mentally ill by a criminal justice system that doesn't have enough qualified professionals to diagnose them.
B) people diagnosed as mentally ill have died or left the system but were not removed from the jail and prisoner count.
C) newly admitted offenders are uneducated and are mistakenly counted as mentally ill.
D) mentally ill people are susceptible to being arrested because they have no shelter and treatment on the streets.