Answer: A. To help commercial banks
Step-by-step explanation:
The Federal reserve bank is the central bank of the United States and the main role of central banks in an economy is to regulate commercial banks. This regulation also means that the central bank has to step in to help these commercial banks if they are going through times of distress.
The reason for this is that commercial banks are very important in the economy as they are key to the financial system. The failure to help commercial banks by the Fed during the Great Depression was one reason the depression lasted as long as it did so now the Fed helps when it can, with conditions of course.