Assume the whole banking system does not hold excess reserves and the required reserve ratio is 20%. If a person withdraws $100 from a bank,
A. The amount of loans made by the banks to the public will fall by at most $400.
B. Money supply will fall by at least $400.
C. The amount of deposits in the banking system will fall by at least $500.
D. The amount of cash reserve of the banks will fall by at most $80.