How are the developmental periods of infancy and adolescence similar?

A) Both involve roughly the same amount of years.
B) Both have a fairly clear-cut boundary for when they begin.
C) Both have a fairly clear-cut boundary for when they end.
D) Most developmentalists study both of these periods at the same time.

Developmental Periods

Phases in the life cycle characterized by specific developmental tasks, milestones, or changes.

Adolescence

The transitional stage of development from childhood to adulthood, characterized by physical, psychological, and social changes.

Infancy

The period in human development extending from birth to 12 months old, characterized by rapid physical and cognitive growth.