Emmet can purchase a $1,000 Municipal Bond with a coupon rate of 4% or a $1,000 Corporate Bond with a coupon rate of 7%. He is in the 37% tax bracket. Which bond will give him the highest after-tax return?

A. The Corporate Bond with a 7% coupon rate

B. The Municipal Bond with a 4% coupon rate

C. They both have the same after-tax return

D. Cannot tell from the information that is given.