You are developing a Windows Azure application in which a web role and worker role will communicate by using a Windows Azure Queue. 
You need to recommend an approach for ensuring that the worker role does not attempt to process any message more than three times. 
What should you recommend？（）

You are designing a Windows Azure application that will process images.  The maximum size of an image is 10 MB.  
The application includes a web role that allows users to upload images and a worker role with multiple instances that processes the images.  
The web role communicates with the worker role by using a Windows Azure Queue. 
You need to recommend an approach for storing images that minimizes storage transactions. 
What should you recommend？ （）