Which bond among the following bonds has the lowest interest rate risk given they all have the same yield to maturity?

	A.	20-year maturity; 6 percent coupon bond
	B.	20-year maturity: 4 percent coupon bond.
	C.	15-year maturity; 4 percent coupon bond.
	D.	15-year maturity; 6 percent coupon bond
	E.	10-year maturity; 4 percent coupon bond.
	F.	10-year maturity; 6 percent coupon bond.