The Money Supply Process Focuses on the Monetary Base Rather

The money supply process focuses on the monetary base rather than on bank reserves because

A) bank reserves have little connection to the money supply.
B) the Fed has better control of the monetary base than it has on bank reserves.
C) bank reserves are difficult to measure.
D) banks are not required to report the level of their reserves, which makes it difficult for the Fed to use them to control the money supply.