A nurse is reinforcing teaching with a group of parents about adolescent suicide. Which of the following findings poses the highest risk of suicide completion in adolescents?

A. While loss of family income can contribute to stress and depression, it is not the highest risk factor for suicide. B. Parental substance use disorder can increase the risk of suicidal behaviors in adolescents, but not as significantly as mental health disorders. C. Parental divorce can be a stressor, but it is not the highest risk factor for suicide completion. D. Bipolar disorder significantly increases the risk of suicide in adolescents due to the severe mood swings and potential for depressive episodes.