In the month of October, DEF Restaurant agreed to cater luncheons for Augusta University for $21$ days at a fixed rate of $$700$ per day. As of the end of the month, $12$ days of services have been provided but not yet billed. The adjusting journal entry on October $31$st would

a$.$

debit Cash $$6,300$ and credit Accounts Receivable, $$6,300.$

b$.$

debit Cash, $$8,400$ and credit Accounts Receivable, $$8,400.$

c$.$

debit Accounts Receivable, $$8,400$ and credit Catering revenue, $$8,400.$

d$.$

debit Accounts Receivable, $$700$ and credit Catering Revenue, $$700.$

e$.$

debit Accounts Receivable $$8,400$ and credit Unearned Revenue, $$8,400.$