For question 13, consider the graph below which illustrates the "Average Tax Rate" as a function of income which results from an income tax in Country A, Country B, and Country C. ATR in Country A ATR in Country B ATR in Country C Income 0 13. It appears that the income tax in Country A is a tax, the income tax in Country B is a tax, and the income tax in County C is a A. progressive; progressive; regressive. B. progressive; regressive; proportional. C regressive; progressive; proportional. D regressive; regressive; proportional