问题如下：
Regarding fixed income indexes, which of the following descriptions is least accurate ?
选项：
A. There are various types in the composition of fixed income indexes.
B. It is difficult and expensive for fixed income portfolio managers to replicate a fixed income index.
C. The data of fixed income securities are relatively easy to get because the securities are often liquid.
解释：
C is correct.
Index providers must depend on dealers for fixed income security prices and the securities are illiquid. So data are relatively difficult to get.
请问老师，B选项怎么解释？为啥不选B？