An organization has deployed an AI system that initially performs well but whose outputs deteriorate...

Output deterioration despite stable inputs is a classic indicator of model drift—specifically concept drift, where the underlying relationships between inputs and targets change over time even when the distribution of inputs appears stable. This requires ongoing monitoring and systematic recalibration.

Why D is Correct: The ISACA AAIR life cycle management guidance identifies continuous performance monitoring and scheduled recalibration as the appropriate response to model drift. Monitoring provides early warning when performance degrades below thresholds, while scheduled recalibration ensures the model is periodically updated to reflect current real-world patterns. This systematic approach prevents continued deterioration and maintains model reliability.

Why A is Wrong: Source code audits and peer reviews address development quality and code integrity, not model drift. Drift is a statistical phenomenon driven by changing data relationships, not code defects that code reviews can identify.

Why B is Wrong: Replacing predictive AI with static rule-based systems eliminates the adaptive capabilities that make AI valuable. Static rules cannot respond to evolving patterns and typically perform worse in dynamic environments.

Why C is Wrong: Dataset cleansing addresses data quality for model retraining but does not establish the ongoing monitoring mechanism needed to detect future drift. A one-time cleansing activity cannot prevent recurrent deterioration.