Choice "A" is correct. Relationships involving income statement accounts tend to be more predictable than relationships involving only balance sheet accounts because income statement accounts represent transactions over a period of time, whereas balance sheet accounts represent amounts as of a point in time. As a result, analytical procedures are more appropriate for operating expense accounts.
Choice "b" is incorrect. Payroll and benefit liabilities are generally recalculated and are a balance sheet account.
Choice "c" is incorrect. Acquisition and disposal of fixed assets are generally vouched to supporting documentation. Fixed assets is a balance sheet account.
Choice "d" is incorrect. Long-term debt transactions are generally vouched to supporting documentation. Long-term debt is a balance sheet account.