Answer:
B. 
Step-by-step explanation:
We are given that,
The expression representing the amount of the loan with 6% interest rate is,
Loan amount =
=
Now, we want to find the amount which represents the loan being compounded monthly.
Thus, we have that,
Loan amount compounded monthly = 
i.e. Loan amount compounded monthly = 
i.e. Loan amount compounded monthly = 
Hence, the expression representing the monthly interest rate on the loan is
.
So, option B is correct.