问题如下：
For an independent central bank, which of the following best describes the advantage of monetary policy?
选项：
A. Monetary policies can be implemented quickly than fiscal policies.
B. Political pressures can not influence fiscal policies but can affect monetary policies.
C. Monetary policies may be also effective when combating a deflationary economy.
解释：
A is correct.
Fiscal policies are subject to recognition,action and impact lags while monetary actions may face fewer lags to taking action than fiscal policies.
考点： advantage of monetary policy
解析：相比较财政政策存在多种时滞的情况，货币政策相对效果会更快点。所以A选项入选。
政治压力不仅会影响财政政策，同时还会影响货币政策。所以B选项不入选。
面对通缩的时候，货币政策往往不够有效，因为大多数情况下利率最低只能调成0，所以C选项不入选。
选项C不是可以实施QE来解决吗？为什么不能选？
