bull 是牛市 利率是上升的 ， 为什么答案是两年期的利率 下降？

问题如下：

A fixed-income trader expects a bull flattening of the interest rate term structure, and wants to pursue a strategy that would profit from this movement in rates. The trader decides to achieve this goal by taking positions in 2-year and 10-year bonds. Will the 2-year rate increase or decrease in the trader’s expected scenario, and which of the following sets of trades would be the most likely to generate a profit if the trader’s expectations materialize?

选项：

A.2-year rate Decrease; Short the 2-year and buy the 10-year B.2-year rate Decrease; Buy the 2-year and short the 10-year C.2-year rate Increase; Short the 2-year and buy the 10-year D.2-year rate Increase; Buy the 2-year and short the 10-year

解释：

A is correct. A bull flattening occurs when long-and short-maturity rates both move down, but long-maturity rates move down by more than short-maturity rates. If the trader expects a bull flattening, the trader can buy the 10-year bonds and short the 2-year bonds. If the trader is right, the 10-year bonds will increase in value relative to the 2-year bonds, and the trader will make money.

B, C, and D are incorrect.