$1.$The balance in the prepaid rent account before adjustment at the end of the year is $$12,000$

and represents three months' rent paid on December $1.$ The adjusting entry required on

December $31$ is

a$.$ debit Prepaid Rent, $$4,000$; credit Rent Expense $$4,000.$

b$.$ debit Prepaid Rent, $$8,000$; credit Rent Expense, $$8,000.$

c$.$ debit Rent Expense, $$12,000$; credit Prepaid Rent, $$12,000.$

d$.$ debit Rent Expense, $$4,000$; credit Prepaid Rent, $$4,000.$