You are designing a Windows Azure application that will generate events for multiple clients. Client web services might be behind NAT gateways.  You need to recommend an approach that will allow you to broadcast the events to clients.  What should you recommend？（）

• A、 Use ADO.NET Data Services and provide a shared key to clients.
• B、 Use Windows Azure Queues and provide a shared key to clients.
• C、 Use Windows Azure Table storage and providea shared key to clients.
• D、 Use the Windows Azure AppFabric Service Bus and provide a shared secret to clients.