In CodePipeline, the service designed to run builds, execute unit/integration tests, and produce build artifacts (including test reports) is AWS CodeBuild. CodeBuild runs commands specified in a buildspec.yml file and supports reporting outputs such as test results (for example, JUnit XML), code coverage, and other build metadata.
Option A is correct because the developer can configure the CodeBuild project to run the test suite during the build phase and configure the buildspec to publish test report files. This integrates naturally into CodePipeline as a build stage, and the reports are generated consistently on each pipeline execution.
Option B is incorrect: CodeDeploy is for deploying applications (in-place/blue-green) and lifecycle hooks, not for standard build/test report generation.
Option C increases operational overhead by managing an EC2 build server, which is unnecessary when CodeBuild provides managed build environments.
Option D is unrelated: CodeArtifact is a package repository, not a test reporting solution.
Therefore, use CodeBuild and configure test reports via the buildspec.
