问题
单项选择题
Open market purchases:（）
A. inject additional reserves into the banking system and increase the money supply.
B. inject additional reserves into the banking system and decrease the money supply.
C. remove reserves into the banking system and increase the money supply.
答案
参考答案：A
解析：
When the central bank pays for the securities that it purchases, the payments increase the monetary base and increase the money supply.