Final answer:
The Social Security tax is a regressive tax because high-income earners pay a smaller percentage of their income than lower-income earners; earnings above $113,000 are not taxed at all. The correct option is 2) Regressive
Step-by-step explanation:
The Social Security tax is an example of a regressive tax structure because as the tax base increases, the taxes paid also increase, yet the marginal tax rate decreases for those above a certain income threshold. Specifically, the Social Security tax becomes regressive because income above $113,000 is not taxed at all, which means that, as a percent of total income, the Social Security tax impacts lower-income earners more heavily than wealthier individuals.
This is distinct from a progressive tax, like the federal income tax, where higher earners pay a higher share of taxes relative to their income. The Medicare payroll tax, on the other hand, is a proportional tax, with everyone paying the same rate regardless of income. The correct option is 2) Regressive