患者，男性，35岁，近一周出现发热、头痛、食欲不振，外生殖器出现溃疡样改变，到皮肤科就诊，实验室检查：HAVIgG抗体阳性，梅毒螺旋体特异性抗体阳性，HIV抗体阴性。

恰当的治疗是（）。

A.大剂量青霉素

B.氯喹

C.干扰素

D.氟康唑

E.利巴韦林

An investor purchased a 10 - year zero-coupon bond with a yield to maturity of 10 percent and a par value of $1000. What would her rate of return be at the end of the year if she sells the bond Assume the yield to maturity on the bond is 9 percent at the time it is sold and annual compounding periods are used.（）

A. 16.00%.

B. 17.63%.

C. 19.42%.