Option C (Continuously monitor key risk indicators):Continuously monitoring key risk indicators (KRIs) ensures real-time visibility of changes in the attack surface, allowing for prompt identification of unexpected systems and minimizing risk.
Option A (Update the risk profile):Updating the risk profile reflects current risks but does not actively prevent the reoccurrence of unexpected systems.
Option B (Minimize errors in metrics):Reducing errors in metrics is useful for accuracy but does not directly address attack surface management.
Option D (Reduce assessment costs):Reducing costs does not mitigate or prevent the reoccurrence of external- facing systems.
References:
CompTIA CASP+ Exam Objective 1.4:Conduct ongoing monitoring of the attack surface and risk indicators.
CASP+ Study Guide, 5th Edition, Chapter 2, Risk Management and Continuous Monitoring.