Restrictions imposed by the client, Rex company, prohibit the confirmation of accounts receivable by direct communication with debtors. These receivables account for 30% of all assets and alternate audit procedures cannot be applied, although the independent auditor was able to examine satisfactory evidence for all other items in the financial statements. The independent auditor should issue a(an:

a. Disclaimer of opinion. b. Adverse opinion. c. Qualified opinion. d. Partial disclaimer of opinion.