One of the three major concerns of developmental psychology involves a focus on

1. Nature and nurture.

2. Continuity and stages.

3. Stability and change.

Explanation:

Developmental psychology is the scientific study of how and why human beings change over the course of their life. Developmental psychology currently focuses in the entire human being lifespan.

Developmental psychology examines our physical, cognitive, and social development and it focuses on three major issues:

Nature and nurture: How does our genetic inheritance (our nature) interact with our experiences (our nurture) to influence our development? Continuity and stages: What parts of development are gradual and continuous? What parts change abruptly in separate stages? Stability and change: Which of our traits persist through life? Which traits of characteristics of ourselves change as we grow older?

So, the question is asking for one of the three major concerns of developmental psychology but since there are no options given, I've given you the three major concerns which developmental psychology focuses in.