The correct answer is Unit test.

A Unit test focuses on a single code component and exercises its logic while isolating it from external dependencies. Teams typically use test doubles such as mocks or stubs so the component can be validated without invoking databases, network services, or other modules, and that isolation makes Unit test the right approach for the described continuous integration pipeline.

Integration test is incorrect because integration tests exercise interactions between multiple components or services and therefore do not isolate a single component from its external dependencies.

Acceptance test is incorrect because acceptance tests validate end to end business requirements and user workflows and they usually involve many integrated components rather than isolating one unit.

Performance test is incorrect because performance testing measures throughput and latency under load and it typically uses realistic environments and dependencies instead of isolating a single component.

Sanity test is incorrect because sanity tests are quick checks to see if a build is stable enough for further testing and they do not provide the focused, isolated verification of a single code component that unit tests do.

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