问题
单项选择题
Which of the following policy tools is the least likely to be available to the U. S. Federal Reserve Board（）
A. Setting the discount rate at which banks can borrow from the Federal Reserve.
B. Requiring the banking system to tighten or loosen its credit policies.
C. Increasing or decreasing bank reserve requirements.
答案
参考答案：B
解析：
The U. S. Federal Reserve can encourage or persuade banks as a whole to tighten or loosen their credit policies, but it cannot compel them to do so.