毛状口腔粘膜白斑是什么病的口腔表现（）
A.普文综合征
B.莱氏综合征
C.斯－约二氏综合征
D.AIDS
E.色素沉着－肠息肉综合征
参考答案：D
A fixed income portfolio manager is evaluating investments in the mortgage market but is concerned about prepayment risk. The security that will most likely minimize prepayment risk is.（）
A. mortgage passthrough security.
B. a portfolio of interest-only mortgage loans.
C. tranche B of a collateralized mortgage obligation.
哪些林木采伐必须办理林木采伐许可证？
