NO.PZ2016010801000087
问题如下：
Which of the following is not the limitation of monetary policy?
选项：
A.It may fail when the economy is in deflation.
B.It is based on the assumption that money neutrality holds
C.In a situation of liquidity trap, monetary policy is hard to work.
解释：
B is correct.
If money neutrality holds, monetary policy and policy rate will have no effects on GDP growth. It is not the reality as monetary policy can impact the real economic growth. Deflation and liquidity trap will limit the effects of monetary policy.
考点：中性利率
解析：如果货币中性成立，那么货币政策和政策利率将不会对GDP增长产生影响，这不是货币政策的缺点，因为我们通常假设货币中性在短期是不成立的。所以B选项入选。
当一国经济处于通货紧缩的时候，特别是处在流动性陷阱的时候将限制货币政策的效果。A,C选项不选。
还有一个Limitation是短期利率的变化可能不能传导给长期利率（因为人们对Inflation的expectation），这个不就是货币中性说的意思吗？
货币中性说MS只会带来物价上涨，影响名义利率，长期对实体经济没有影响（real output, employment）
