Answer:
A. Net reserves will increase by $100
Step-by-step explanation:
In both the cases the reserves will increase because when the investor sells the $100 bond to the central bank, the bank would debit securities by $100 and would credit the reserves by $100
In case the investor may cash it or deposit the amount she receives the banking system would debit $100 securities and credit $100
Eventually it would mean that either way the amount from the bond sold would still stay with the bank and stay in circulation which would therefore increase the reserves by $100. There would be no change in currency and the monetary base will increase by $100