Answer: The correct answer is choice d - regressive income tax.
Explanation: This is an example of a regressive income tax. A regressive tax is one that takes a higher percentage of tax on low income earners than on higher income earners.
George is paying 15% interest on earnings of $50,000 (7,500 / 50,000 = .15). Julia is paying 11.25% on earnings of $80,000 (9,000 / 80,000 = .1125).
Because George is paying a higher percentage of tax on a lower income this is classified as a regressive tax.