Answer:
The correct answer is option 4.
Step-by-step explanation:
The banks do not hold any excess reserves.
The required reserve ratio is 20%.
Sarah deposits $5,000 in cash in her checking account.
The banks reserves will increase by
= $5,000 - 20% of $5,000
= $5,000 - $1,000
= $4,000
This will cause the money supply to increase by
=

=

= $20,000