Those Who Study Human Development and the Aging Process Support

Those who study human development and the aging process support the notion that aging is a process of both nature and nurture, and that the two forces interact to create a unique individual. In particular, there are four interactive forces of development, one of which is "psychological forces." Which of the following explains this force?

A) These refer to all genetic and health-related factors. For example, is a person genetically predisposed to getting cancer? Also included in this area of development are lifestyle choices such as diet, exercise, whether a person smokes or not, and alcohol consumption.
B) These forces include cultural, ethnic, societal, relational, and interpersonal factors. In this area of development, family scientists consider things among the aging population such as employment, living arrangements, marital status, parenting and grandparenting, and caregiving.
C) All of the forces interact and combine to create a person's unique, individual developmental experiences.
D) These refer to all cognitive, emotional, and perceptual factors. Among the aging, things such as cognitive impairment due to certain diseases, and memory loss and retention are considered.