A team is developing an application for end users. The application will use microservices. For user access dual-factor authentication will be used. Which type of test must be performed by the CI/CD to

Unit tests verify individual code components in isolation and do not cover interactions between multiple services or replicate complete user workflows.

End-to-end (E2E) tests are specifically designed to simulate real user behavior by testing the entire application flow from start to finish, across all integrated microservices, user interfaces, and authentication mechanisms like dual-factor authentication. This verifies that all components work together seamlessly to support various user actions and deliver the expected outcomes, confirming the application's overall functionality and user experience.

A/B tests are used for comparing different versions of a feature to optimize user experience or performance, not for verifying that core user actions function correctly within the application.

Sanity tests provide a quick check of critical functionalities to determine if a build is stable enough for further testing, but they do not thoroughly replicate diverse user behaviors or verify a wide range of user actions.