Which intervention has the highest priority when caring for an adolescent diagnosed with attention-deficit/hyperactivity disorder (ADHD) who has poor judgment, high risk-taking behaviors, and impulsivity?

Develop and sign a "no self-harm" contract with the teenager.

Assign a staff member to one-to-one observation until the treatment team determines the teenager is no longer at risk for harm.

Schedule frequent discussions between the nurse and teenager to explore stressors, coping skills, and behavioral alternatives.

Implement locked seclusion until the teenager is able to identify examples of good judgment and control impulsive reactions.