Final answer:
The City of Mayville should report a restricted fund balance of $42,000 in its General Fund as of December 31, 2019, which corresponds to the grant funds allocated for purchasing musical instruments that have not been used.
Step-by-step explanation:
Understanding Restricted Fund Balance for Mayville
The restricted fund balance in the General Fund refers to the portion of the total fund balance that is subject to constraints imposed by external parties, constitutional provisions, or enabling legislation. For the City of Mayville, the grantor provided $42,000 specifically to be used to purchase musical instruments for the city's youth orchestra. Since the funds have not been used yet and are restricted for a specified purpose, this amount should be reported as the restricted fund balance.
Therefore, the correct answer to the amount that should be reported as restricted fund balance in the General Fund on December 31, 2019, is $42,000 (Option A). The outstanding encumbrances and prepaid items such as inventory and rent do not impact the restricted balance, as they relate to different parts of the fund balance (e.g., committed, assigned, or unassigned).