You are designing a Windows Azure application.   The application will include services hosted in different geographic locations.  The service locations may change.   You must minimize the cost of communication between services.  You need to recommend an approach for calling the services.  What should you recommend？（）

• A、 Use the Service Management API.
• B、 Use Windows Azure Table storage.
• C、 Use Windows Azure Queue storage.
• D、 Use the Windows Azure AppFabric Service Bus.