Given a Nominal Interest Rate of 5 Percent,in Which Case

Given a nominal interest rate of 5 percent,in which case below would you earn the highest after-tax real rate of interest?

A) Inflation is 3 percent; the tax rate is 20 percent.
B) Inflation is 2 percent; the tax rate is 40 percent.
C) Inflation is 1 percent; the tax rate is 60 percent.
D) The after-tax real interest rate is the same for all of the above.