The balance in the prepaid rent account before adjustment at the end of the year is $$11,976,$ which represents four months' rent paid on December $1.$

The adjusting entry required on December $31$ is

a$.$ debit Rent Expense, $$8,982,$ credit Prepaid Rent, $$2,994$

b$.$ debit Prepaid Rent, $$2,994,$ credit Rent Expense, $$2,994$

c$.$ debit Prepaid Rent, $$8,982,$ credit Rent Expense, $$2,994$

d$.$ debit Rent Expense, $$2,994,$ credit Prepaid Rent, $$2,994$