According to a major study on violent activity among former psychiatric patients, which of the following groups had the lowest rate of violent activity?
A) Former patients with a major mental disorder and a history of substance abuse
B) Former patients with a major mental disorder without a history of substance abuse
C) Former patients with a diagnosis of "other" mental disorders and a co-occurring substance abuse problem
D) Former patients with a diagnosis of adjustment disorder and a co-occurring substance abuse problem