The tax incidence being shifted disproportionately to those with higher incomes describes which tax structure?

The correct answer is based on the nature of a progressive tax structure, which is designed so that individuals with higher incomes pay a larger percentage of their income in taxes compared to those with lower incomes. This method of taxation is rooted in the ability-to-pay principle, which posits that those who have more financial resources should contribute a larger share to fund public services and obligations.

In a progressive tax system, tax rates increase as income increases. This means that as a person's income rises, they can afford to pay a higher rate, which helps to reduce income inequality by redistributing wealth throughout the economy. The tax burden is thus shifted disproportionately to those with higher incomes, reflecting an intentional policy choice to ensure that the wealthier citizens contribute more to government revenue.

In contrast, regressive taxes tend to take a higher percentage of income from low-income earners compared to high-income earners, flat rate taxes apply the same tax rate to everyone regardless of income, and nominal rate taxes focus on the stated rate without adjusting for the taxpayer's income levels. Each of these other structures has distinct characteristics that do not align with the principle of shifting the tax incidence primarily onto those with higher incomes.