B和C的区别是什么

问题如下：

The bond issue trading at the highest bid–offer spread is most likely a:

选项：

A.

recently issued sovereign bond.

B.

seasoned investment-grade corporate bond.

C.

recently issued investment-grade corporate bond.

解释：

B is correct. Bonds of less frequent corporate issuers or more seasoned bonds of frequent issuers are rarely traded, leading dealers to quote bid–offer spreads of at least 10–20 basis points or more for small sizes. The most recently issued, or on-the-run, developed market sovereign bonds are typically the most liquid fixed-income securities, with primary dealers making active markets in large size with bid–offer spreads equal to a fraction of a basis point. Among corporate issuers, recently issued corporate bonds from frequent issuers of higher credit quality usually exhibit the greatest liquidity and tightest bid–offer spreads.