Which of the following statements is correct?
A. As a public transfer payment, Social Security benefit is available only to the poor.
B. Social Security benefits are received by people who had contributed to the fund during their active work years.
C. The Social Security program funnels transfers from retired individuals to the youngest children of low-income families.
D. Social Security is an entitlement which is available to everyone, including those who have not contributed to the fund during their active work years.