Why Do Consumers Benefit from Pay-As-You-Go Social Security

Why do consumers benefit from pay-as-you-go social security?

A) It keeps inflation in check as money is redistributed.
B) It is a better way than taxes to finance the government.
C) It forces people to save more than they would otherwise.
D) With sufficiently high population growth, many young contribute to the benefits of the old.
E) With sufficiently low population growth, the young can perpetually contribute more.