An auditor placed a high reliance on the IT system of a public company. The IT system includes key internal control. As a result, significant proportion of the audit was focused on this area at the regional and international levels, including the company's data center. The auditor focused on understanding and validating the impacts of key changes that were being made to the control environment.

Because of these circumstances, the auditor is likely to:

A$.$

Write a disclaimer of an opinion because of a scope limitation in testing the controls over the data centers. This disclaimer is not subject to the response by management.

B$.$

Include a a significant deficiency in their audit report, because the reliance on the control was not tested.

C$.$

Include a Key Audit Matter $($KAM$),$matter in their audit report, because this was not an area of additional focus for the auditor.

D$.$

Include a Critical Audit Matter $($CAM$)$ in their audit report, because this was an area of additional focus for the auditor.