As Part of a Nightly Testing Process, New Version of an Application

As part of a nightly testing process, new version of an application is deployed to the set of web servers in the development environment. Which of the following is the BEST way to ensure the test environment is consistent with the previous night's test?

A) Clone the development web servers to the test environment.
B) Reprovision the web servers using predefined templates.
C) Undeploy the previous application and deploy the new version.
D) Revert to a previous state using configuration management tools.