The balance in the Prepaid Rent account before adjustment at the end of the year is $$25500,$ which represents three months' rent paid

on December $1.$ The adjusting entry required on December $31$ is to

debit Prepaid Rent, $$8500$; credit Rent Expense, $$8500.$

debit Rent Expense, $$17000$; credit Prepaid Rent $$17000.$

debit Prepaid Rent, $$17000$; credit Rent Expense, $$17000.$

debit Rent Expense, $$8500$; credit Prepaid Rent, $$8500.$