Which of the following is an SDLC best practice that should have been followed?

The director of sales asked the development team for some small changes to increase the usability of an application used by the sales team. Prior security reviews of the code showed no significant vulnerabilities, and since the changes were small, they were given a peer review and then pushed to the live environment. Subsequent vulnerability scans now show numerous flaws that were not present in the previous versions of the code.

Which of the following is an SDLC best practice that should have been followed?
A . Versioning
B . Regression testing
C . Continuous integration
D . Integration testing

Answer: B