The most likely tax that follows the principle that states that people should pay based on their ability is the federal income tax. This tax is progressive as the high income earners pay a higher percentage as tax when compared to he low income earners.
The sales tax and doctors license fees aren't progressive, as the rich and the poor all pay same amount. This doesn't align with the principle.
B is not an example of economic freedom because wages and prices are being controlled by the gov. controlling money is not freedom economically because the individuals are not controlling it themselves (which would be freedom) . The rest of the options are examples of economic freedom.
