The following transactions for the month of March have been journalised and posted to the proper accounts.

Mar 1 Martinez invested $10,000 cash in his new design services business.

Mar 2 Paid the first month's rent of $500.

Mar 3 Purchased equipment by paying $1000 cash and executing a loan payable for $5000.

Mar 4 Purchased office supplies for $750 cash.

Mar 5 Billed a client for $11,000 of design services completed.

Mar 6 Received $7000 on account for the services previously recorded.

What is the ending balance in the Service revenue account?

A) $17,000 B) $10,000 C) $7000 D) $11,000