If the Fed Purchases $50,000 in T-Bills from a Bank,by

If the Fed purchases $50,000 in T-bills from a bank,by how much will the bank's excess reserves increase?

A) by $50,000
B) by $50,000 times the required reserve ratio
C) by $50,000 divided by the required reserve ratio
D) Not enough information has been provided to answer the question.