Given a Nominal Interest Rate of 8 Percent, in Which

Given a nominal interest rate of 8 percent, in which of the following cases would you earn the highest after-tax real interest rate?

A) Inflation is 5 percent; the tax rate is 20 percent.
B) Inflation is 4 percent; the tax rate is 30 percent.
C) Inflation is 3 percent; the tax rate is 40 percent.
D) The after-tax real interest rate is the same for all of the above.