The issue could have been avoided if the developer had used Sandbox testing (Option D), which allows new software to be tested in a controlled environment before implementation. This process ensures that the software does not negatively impact system functionality, like stopping access to critical resources such as file servers. * End-user acceptance (Option A) ensures that users approve the software, but it wouldn't prevent the issue. * Staff delegation (Option B) relates to who is responsible but doesn't address testing. * Appropriate scoping (Option C) helps in defining the extent of changes but does not replace testing. CompTIA A+ Core 2 References: * 4.2 - Explain basic change management best practices, including testing in a sandbox environment.