这道题是否可以不计算，从理解的角度直接做

问题如下：

The portfolio alternative with the highest modified duration is the:

选项：

A.

bullet portfolio.

B.

barbell portfolio.

C.

equally weighted portfolio.

解释：

B is correct. The modified duration of a fixed-income portfolio is approximately equal to the market value-weighted average of the bonds in the portfolio, so the barbell has a modified duration of 5.049, or (1.922 + 8.175)/2), which is larger than that of either the bullet (4.241) or the equally weighted portfolio (4.779, or (1.922 + 4.241 + 8.175)/3