55. What is the main idea of the passage? [
(A)] Most old people live longer today after an illness than people did years ago. [
(B)] Many old people are put into nursing homes by their families, who do not visit them regularly. [
(C)] Most elderly people are taken care of by their families, who assume the responsibility for different reasons. [
(D)] Most elderly people are satisfied with the better ways of caregiving that social workers have come up with.