The correct answer is Cloud Build. While Cloud Source Repositories provides a private Git repository for source code management, it lacks dedicated CI/CD capabilities. Cloud Functions is a serverless compute platform for event-driven functions, not a CI/CD platform. Cloud Deployment Manager aids in infrastructure provisioning through declarative configurations but doesn't offer native CI/CD features. Cloud Build, however, is specifically designed as a fully managed CI/CD platform in GCP, enabling the definition of build pipelines, automated builds triggered by source code changes, and seamless integration with other GCP services for comprehensive continuous integration and delivery solutions.