An administrator is looking to apply a new service pack for an OS on several systems that run business critical applications for a large international finance corporation. Which of the following should the administrator do FIRST?（）

• A、Deploy the service pack to a single department within the corporation.
• B、Upgrade the system with requirements for that service pack.
• C、Deploy the service pack to a non-critical application server.
• D、Submit a change control for the service pack deployment.