What baseline Change Model would be suitable for capturing changes from an external system for reporting purposes?

The suitable baseline Change Model for capturing changes from an external system for reporting purposes is Change Registration. This model focuses on systematically recording and documenting changes, which is essential for creating accurate reports. Change Registration enables organizations to track modifications initiated from various sources, including external systems, thereby ensuring that all relevant changes are logged comprehensively.

Through this model, data regarding what changes occurred, when, and their implications can be recorded effectively, allowing for thorough analysis and reporting. This capability is critical for maintaining transparency and ensuring compliance with organizational policies as well as regulatory requirements. It provides a clear audit trail that can be invaluable during reviews or audits, enhancing accountability within the change management process.

In contrast, other options such as Cloud Infrastructure, Automated Changes, and Retroactive Changes either pertain to specific types of changes or processes within the IT infrastructure that don't cover the broad requirements of externally sourced change documentation needed for reporting. This differentiation solidifies why Change Registration is the correct choice for the purpose outlined in the question.