Which of the following describes the waterfall typically used for mortgages pre-crisis? A: A distribution of cash flows to tranches with priority given to tranche with the highest rating B: A distribution of cash flows to tranches in proportion to their outstanding principals C: A distribution of losses to tranches so that tranches bear losses in proportion to their outstanding principals D: None of the above

下列关于采用资产投资额度方式进行信用增级的表述中，不正确的是（） A: 资产投资额度是通过发行C档（C Tranche）债券，引进次级投资者进行增信 B: 资产投资额度是由卖方或第三方存入资金到信托账户进行增信 C: 资产投资额度优先级低于其他优先级证券 D: 资产投资额度是在超额利差降为负数时用来填补其他证券的利息和本金等的付款不足