问题如下：
If a central bank increases the reserve requirements, which of the following statements is least correct?
选项：
A.The central bank restricts money creation.
B.A contractionary monetary policy is used.
C.The supply of money will increase.
解释：
C is correct.
Raising reserve requirements should limit the supply of money. It also refers to a contractionary monetary policy.
考点： reserve requirements
解析： reserve requirements 是央行要求商业银行需要存放在其那里的现金。
如果 reserve requirements 增加，那就表明商业银行需要把更多的货币放到央行那儿，那么货币制造就会减少，货币供给也相应减少，这是一种紧缩的货币政策，所以C选项入选。
B选项就是紧缩的货币政策，答案解析也是选择紧缩的货币政策。为什么b不对？
