问题如下：
During a recession, the slope of the yield curve for default-free government bonds is most likely to:
选项：
A. flatten.
B. steepen.
C. become inverted.
解释：
B is correct.
During a recession, short rates are often lower because central banks tend to lower their policy rate in these times because the output gap is likely to be negative. However, the impact of such monetary policy on longer-term rates will not be as strong, so long rates may not fall by as much as short rates. The central bank will usually be expected to bring short term rates back to normal as the recession recedes and the risk free rates will increase as economic growth recovers. Thus, the slope of the yield curve will typically steepen during a recession.
考点：yield curve
解析：关键词During a recession，在经济衰退期，yield curve是变陡峭的，因为央行会降息，降息对短期利率的影响更大，导致yield curve steepen.
另一个结论是：An inverted yield curve is a predictor of recession。注意区分。
题目说的是 slope（收益率曲线的斜率）变陡峭，解析是yield curve 变陡峭，这俩不是一回事儿吧？
