Which code fragment should you use?

You are creating a client application by using Microsoft .NET Framework 3.5.
The client application will consume a COM+ application by using the Windows Communication Foundation service.
You write the following code segment to implement the COM+ application.

[Guid("InterfaceGuidsHere")]
public interface IDocumentStore
{
bool lsDocumentExist(long id);
}
[Guid("ClassGuidsHere")]
public class DocumentStore: servicedComponent, IDocumentStore
{
public bool IsDocumentExist(long id)
{
//This code checks if document exists.
}
}

The application ID of the COM+ application is {AppGuidsHere}.
You need to configure the WCF service to access the COM+ application from the WCF client application.
Which code fragment should you use?

A.
<services>
<service name="{AppGuidsHere},{ClassGuidsHere}">
<endpoint binding="wsHttpBinding" contract="IDocumentStore"/>
</service>
</services>

B.
<services>
<service name="{AppGuidsHere},{ClassGuidsHere}">
<endpoint binding="wsHttpBinding" contract="{InterfaceGuidsHere}"/>
</service>
</services>

C.
<services>
<service name="{AppGuidsHere},{ClassGuidsHere}">
<endpoint binding="wsHttpBinding" contract="DocumentStorage.IDocumentStore"/>
</service>
</services>

D.
<services>
<service name="{AppGuidsHere}">
<endpoint binding="wsHttpBinding" contract="{InterfaceGuidsHere}"/>
</service>
</services>