According to the passage, what is essential to successful aging

A．They get married before they buy their own house.
B．More people get divorced and do not remarry soon.
C．They attend local colleges so they have to stay home.
D．They move back so that they can take care of their parents.

A．They are likely to be annoyed if they are not.
B．They may give the bride valuable presents.
C．Their presence could provide future benefits.
D．They may help with the expenses of the wedding.