The word "it" in the last paragraph refers to ______ .

A．the human body can't be compared to a car
B．the older a person, the more care he needs
C．too much emphasis has been put on old people's values
D．it is easy to provide spare parts for old people

A．there are both advantages and disadvantages to being rich
B．traveling a lot will be beneficial to children
C．rich children usually have little confidence in themselves
D．rich kids are often short of money because of their life of luxury