You are planning the migration of an existing application to Windows Azure and SQL Azure. The application produces report files at the request of remote systems. Requests for report files will be placed into a single Windows Azure Queue. You must minimize the compute resources and storage transactions required to process the requests. You need to recommend an approach for processing the requests. What should you recommend？（）

A. Create a worker role for each report file that constantly polls the queue for requests.
B. Create a workerrole for each report file that checks the queue at scheduled intervals for requests.
Create a single worker role that constantly polls the queue for requests and executes the requests on multiple threads.
D. Create a single worker role that checks the queue at scheduled intervals for requests and executes the requests on multiple threads.