During the audit of Zenith Ltd.

During the audit of Zenith Ltd., the external auditor decides to obtain direct assistance from internal auditors.

The external auditor assigns the internal auditors the following tasks:

Selecting samples of sales invoices based on criteria determined by the external auditor.
Examining supporting documents for the selected invoices.
Performing confirmation procedures with selected customers.
Assessing whether a complex revenue arrangement satisfies the relevant revenue-recognition requirements.
Determining whether an identified misstatement is material to the financial statements.
Documenting the procedures performed and the results obtained.

The engagement partner states:

“Since the internal auditors are working under our direction, supervision and review, they may perform all six procedures. The external auditor retains responsibility merely by reviewing their working papers.”

Which ONE of the following is the most appropriate?

A. The partner is correct because direct assistance permits internal auditors to perform audit procedures whenever the external auditor supervises and reviews their work.

B. The partner is incorrect because significant judgements must remain with the external auditor, although internal auditors may perform appropriate procedures under direction, supervision and review.

C. The partner is incorrect because internal auditors providing direct assistance may perform only documentation procedures and cannot perform substantive audit procedures.

D. The partner is correct except that internal auditors cannot perform confirmation procedures because such procedures necessarily require direct involvement of the external auditor.