投资需求曲线（Investment demand curve）

Consider three municipal bonds issued by the Greater Holmen Metropolitan Capital Improvement District, a local authority that carries an issuer rating of single-A from the major debt rating agencies. All three bonds have the same coupon rate and maturity date. Series W was issued to finance the rebuilding and expansion of local schools and is backed by the District’s authority to levy property tax. Series X was issued to build a water purification plant for the region. The District charges fees to the surrounding municipalities for their use of the plant. These fees are the only source of the interest and principal payments on the bonds. Series Y was issued to raise funds for the general use of the District in its ordinary maintenance projects and is backed by the District’s authority to levy property tax. These bonds carry a third party guarantee of principal and interest payments. What is most likely the order of the market yields on these three bond issues, from highest to lowest（）

A. Series Y, Series W, Series X.

B. Series W, Series X, Series Y.

C. Series X, Series W, Series Y.