While following up on a prior audit report, an IS auditor determines that a number of recommendations to address critical findings have not been implemented as agreed. What is the BEST course of action for the auditor? 

Answer options:

A. Reclassify the risk ratings of the original findings.
B. Propose revised implementation timelines.
C. Escalate to the appropriate level of management.
D. Revise the scope of the follow-up audit

C