Final answer:
The field of study focused on the economic, social, and psychological aspects of aging is Gerontology. It is a multidisciplinary subject that includes the evaluation of medical, social, and economic concerns related to older adults. Gerontology is distinct from geriatrics, which is a medical specialty concerning elderly health care.
Step-by-step explanation:
The field of study that examines the economic, social, and psychological aspects of aging is A. Gerontology. Gerontology is a multidisciplinary field encompassing medical and biological sciences, social sciences, and even financial and economic research, all focused on understanding the aging process and addressing the issues faced by senior populations. Social gerontology, in particular, delves into the sociological aspects of aging, such as the mental and physical well-being of older adults and broader societal impacts like the graying of the United States.
In contrast, geriatrics is a medical specialty focusing strictly on the health care of elderly people. Sociology and psychology are broader fields that encompass studies related to many aspects of human behavior and society, which can include but are not specifically focused on aging.