—Do you like Nack?

—Yes, Nack is good, kind, hard — working and intelligent; ________ , I can't speak too highly of him.

A．as a result

B．in a word

C．by the way

D．on the contrary

反映有效组合的收益和风险水平之间均衡关系的方程式是( )。

A．证券市场线方程
B．证券特征线方程
C．资本市场线方程
D．套利定价方程