Which of the following is NOT a stage of the lifespan?

Retirement is not traditionally categorized as a distinct stage of the lifespan. The stages of the lifespan typically recognized in developmental psychology and related fields include infancy, childhood, adolescence, adulthood, and sometimes late adulthood or older age. Each of these stages is defined by specific developmental tasks and milestones that individuals typically achieve as they progress from one stage to the next.

While retirement is an important phase in many people's lives, especially as they transition from full-time work, it is often considered a status or life change rather than a distinct stage of development on the lifespan continuum. This is because retirement can happen at various ages, can differ significantly in its impact depending on individual circumstances, and is not universally experienced in the same way by all individuals. Thus, while it may mark a significant shift in lifestyle and daily activities, it does not represent a broadly recognized developmental stage in the same manner as the other choices do.