Salesforce Developer Development-Lifecycle-and-Deployment-Architect Question # 51 Topic 6 Discussion

 D is the correct answer, as utilizing automated source control, test, and build systems to test and deploy to production can help to maintain quality and reduce the risk of bugs being introduced to production. Automated systems can ensure that the code is consistent, version-controlled, tested, and validated before deploying to production. A is incorrect, as requiring developers to deploy completed code and unit tests directly to production can introduce errors and conflicts, as well as bypass the testing and validation stages. B is incorrect, as deploying all functionality together can create complexity and dependency issues, as well as delay the release of completed features. C is incorrect, as using a spreadsheet to track approved changes that should be released with change sets can be prone to human errors and inconsistencies, as well as lack of automation and integration. You can learn more about this topic in the Continuous Integration and Continuous Delivery module on Trailhead.