______benefits have to be demanded.

A．Flat rate benefits are based on the contributions one has made.
B．One automatically has the right to flat rate benefits regardless of contributions made.
C．If one is out of work, he can get the flat rate benefits.
D．If the government decides one is below the minimum standard of living, supplementary benefits are provided.

A．to claim
B．details of his capital assets and source of income
C．certain number of contribution
D．nothing