The following transactions for the month of March have been journalised and posted to the proper accounts. Mar 1 Martinez invested $7,000 cash in his new design services business. Mar 2 Paid the first month's rent of $600 Mar 3 Purchased equipment by paying $3,000 cash and executing a loan payable for $3,000 Mar 4 Purchased office supplies for $550 cash. Mar 5 Billed a client for $10,000 of design services completed. Mar 6 Received $8,000 for the services previously recorded. What is the balance in Accounts receivable? OA. $4,000 Cr OB, $2,000 Dr OC. $2,000 Cr O D. $4,000 Dr