You are migrating a solution to Windows Azure. The solution includes a web application and a business logic layer. The web application runs on three dual-core servers. The business logic layer runs on two quad-core servers. The Windows Azure application must match or exceed the current hardware specifications. You need to recommend role instance sizes that minimize cost. What should you recommend？（）
- A Small for the web application and Medium for the business logic layer
- B Small for the web application and Large for the business logic layer
- C Medium for the web application and Large for the business logic layer
- D Large for the web application and Extra Large for the business logic layer