Which of the following statements on bond yield is true?

A. When looking at yields for callable bonds, we calculate the current yield instead of yield-to-maturity.

B. The investor does not need to reinvest the coupons to realize the estimated yield-to-maturity.

C. Yield-to-maturity is the net present value of all cash flows from the bond.

D. The yield of a bond may include interest payments, capital gain and income from reinvesting the coupons