问题
单项选择题
Which of the following statements about a central bank's actions would most likely cause an immediate increase of the banking system's excess reserves（）
A. Decreasing the policy rate.
B. Selling securities in the open market.
C. Decreasing the required reserve ratio.
答案
参考答案：C
解析：
降低法定存款准备金率会导致商业银行吸收存款后有更多的资金可以用于放贷，从而增加了银行系统的可贷资金余额，这种影响也最为直接。