In a DevOps environment, which of the following actions is MOST necessary to have confidence in the quality of the changes being made?

Preparing to take corrective actions quickly is a reactive measure that addresses problems after they occur, rather than proactively validating quality before or during the change process.

Receiving approval from a change review board is a traditional ITIL/change management process that introduces manual gates and slows delivery, which is contrary to DevOps principles of continuous integration and delivery.

Reviewing logs for anomalies is a post-deployment monitoring activity that detects issues after changes are already in production, rather than ensuring quality confidence during the development and release pipeline.

Automating functionality testing integrates continuous testing directly into the CI/CD pipeline, ensuring every change is validated against defined functional requirements before deployment. This provides consistent, repeatable, and rapid feedback on code quality without human bottlenecks, which is a foundational DevOps practice for maintaining confidence in releases.