An administrator needs to implement a security patch policy on the network that adheres to an internal SLA. Which of the following actions BEST achieves this task?（）

• A、Define a test server group, install the patches and if successful schedule installation on production servers.
• B、Define a test server group, schedule installation on production servers and then install all updates and patches.
• C、Install the patches during a non-working hour.
• D、Send an email to all company users and request the best time for installation.