A developer is designing a multi-tier web application and discovers a need to hide the details of establishingand maintaining remote communications from the client. In addition， the application needs to find，in a transparent manner，the heterogeneous business components used to service the client’s requests. Which design patterns， working together， address these issues？（）
- ABusiness Delegate and Transfer Object
- BBusiness Delegate and Service Locator
- CFront Controller and Business Delegate
- DIntercepting Filter and Transfer Object