You are designing a Windows Azure application.   The application contains one web role and three worker roles.  You need to recommend an approach for updating only one role without interrupting the other roles.   What should you recommend？（）

• A、 Perform a VIP swap.
• B、 Perform an in-place upgrade.
• C、 Delete the current deployment and then redeploy the application.
• D、 Copy the cloud package to blob storage and then restart the service.