If the following balances are exist in the adjusted trial balance: Service revenues $ 45,000 Interest expense $ 10,000 Salaries Expense $ 30,000 Rent Revenues $ 4,000 Depreciation Expense $ 7,000 Drawings $3,000 The closing entry for the Revenue Accounts should affect the Income summary account as: O a. Income summary account should be Debited (Dr.) by $ 45,000. Ob Income summary account should be Credited (Cr.) by $ 45,000. O Income summary account should be Credited (Cr.) by $ 49,000. O d. Income summary account should be Debited (Dr.) by $ 49,000