A．Became they contributed a small portion in tax but enjoy more on the welfare system.
B．Because they contributed a lot in tax and now can claim much on the welfare system.
C．Because they made small contributions, but now can make money easily.
D．Because they outnumber younger generation and enjoy more privileges in the present society.

A．Many young men, who live alone, have increased demand for houses.
B．Many young men need to rent more houses.
C．It is easy to apply for a mortgage for young generation.
D．The number of older people, many of whom live alone, becomes bigger and bigger.