A small CPA firm provides audit services to a large local company. Almost eighty percent of the CPA firm's revenues come from this client. Which statement is most likely to be true?
A、Appearance of independence may be lacking
B、The small CPA firm does not have the proficiency to perform a larger audit
C、The situation is satisfactory if the auditor exercises due skeptical negative assurance care in the audit
D、The auditor should provide an "emphasis of a matter paragraph" to his/her audit report adequately disclosing this information and then it may issue an unqualified opinion.