西方中央银行常用的货币政策工具是( )。
A．公开市场业务
B．贴现率政策
C．准备率
D．选择性信用管制
参考答案：A
_______ the right to correct his difficult question，the teacher of English was pleased and praised me in front of the class.
A．Having given
B．Having been given
C．To be given
D．Giving
调车线间设有制动员室的线间距离是（）mm。
A.7000
B.6500
C.6000
D.5500
