正解:A
The business case defines the project's expected benefits, success criteria, and performance metrics.
Reviewing the business case allows the auditor to assess whether the benefits identified at initiation have been realized post-implementation. The schedule (B) only tracks timeliness, not value. Proposed enhancements (C) address future improvements, not whether benefits have been delivered. QA results (D) reflect product quality but not business value. ISACA emphasizes that value delivery and benefits realization are key elements of enterprise governance of IT, aligning with COBIT's EDM02 (Ensure Benefits Delivery).
References (ISACA): COBIT 2019, EDM02 Ensure Benefits Delivery.