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 Expense Accounts should affect the income summary account as: O a. Income summary account should be Credited (Cr.) by $ 47,000. O b. Income summary account should be Debited (Dr.) by $ 47,000. OC. Income summary account should be Debited (Dr.) by $ 50,000. O d. Income summary account should be Credited (Cr.) by $50,000