You have been hired as the accountant for Gunner's Pet and Livestock Supplies, Incorporated. At the beginning of the year, net income is estimated to be $80,000. The corporate federal income tax rate is 21%. On December 31, it is determined that net income is $88,000. After adjusting entries have been made, what is the closing entry, if any, related to federal income taxes? a. Debit Income Summary for $1,680 and credit Income Tax Expense for $1,680 b. Debit Income Summary for $18,480 and credit Income Tax Expense for $18,480 c. Debit Income Tax Expense for $18,480 and credit Income Summary for $18,480 d. No entry is required because Income Tax Expense is a permanent account