What is the primary focus of developmental psychology?

The primary focus of developmental psychology is indeed the study of how individuals change and grow throughout their lifespan. This field examines various stages of development, from infancy to old age, and considers physical, cognitive, emotional, and social changes that occur over time. Developmental psychologists explore how these changes are influenced by a variety of factors including genetics, environment, culture, and experiences.

This comprehensive approach enables researchers to understand the processes underlying growth and transition at different life stages, such as childhood, adolescence, adulthood, and aging. By investigating these developmental milestones, psychologists can identify typical patterns of growth as well as variations that may occur due to individual differences or contextual influences.

The other options, while they touch on important aspects of psychology, do not capture the essence of developmental psychology. Analyzing personality traits primarily relates to personality psychology, examining societal norms is more aligned with social psychology, and investigating cognitive therapy techniques falls under clinical psychology. Therefore, the correct answer highlights the unique emphasis of developmental psychology on the lifelong process of human growth and change.