Cynthia has been asked by her boss to check the balance in Accounts Receivable. There are four subsidiary ledgers. Two are for customers: $$9,600$ and $$3,900.$ And the other two are for creditors: $$4,200$ and $$10,500.$ Which of the following would be the correct balance in Accounts Receivable?

$$14,700$

$$13,500$

$$20,100$

$$28,200$