Restrictions imposed by a client prohibit the observation of physical inventories, which account for 35 percent of all assets. Alternative audit procedures cannot be applied, although the auditor was able to examine satisfactory evidence for all other items in the financial statements. The auditor should issue a(an)

a. "Except for" qualified opinion.

b. Disclaimer of opinion.

c. Unqualified opinion with a separate explanatory paragraph.

d. Unqualified opinion with an explanation in the scope paragraph.