Final answer:
Other elderly people provide most of the caregiving to elderly people in the United States.
Step-by-step explanation:
The category of people in the United States that provides most of the caregiving to elderly people is other elderly people. According to research, in the United States, many middle-class families are unable to afford professional healthcare for their elderly family members. As a result, the responsibility often falls on other elderly family members to provide the necessary care and support. Additionally, it is important to note that different demographic groups in the United States have different approaches to aging and caregiving.