A nurse in an emergency department is caring for an adolescent following a suicide attempt. After reviewing the client's history, the nurse should determine which of the following is the priority risk factor for suicide completion.

A. History of substance abuse: While substance abuse significantly increases the risk of suicidal behavior, it is not as strong a predictor of suicide completion as a previous attempt. Substance use may however contribute to impulsivity and poor judgment. B. Previous suicide attempt: A history of a previous suicide attempt is the most significant risk factor for future suicide completion. It strongly indicates unresolved psychological distress and the potential for repeat behavior. C. Active psychiatric disorder: Psychiatric conditions like depression and bipolar disorder are major risk factors, but a prior suicide attempt is a more direct and statistically stronger indicator of risk for completion. D. Loss of a parent: Parental loss can be traumatic and increase long-term risk for depression or suicidal thoughts, but it is less predictive of imminent suicide risk than a past suicide attempt.