You are creating a Windows Communication Foundation service by using Microsoft .NET Framework 3.5. You want to use a built-in binding to support reliable sessions. You need to create a service that uses SOAP to transfer messages between endpoints. The service must deliver the messages only once, and in the same order in which they were sent. Which type of binding should you use?

A.
BasicHttpBinding

B.
WSDualHttpBinding

C.
NetMsmqBinding

D.
NetPeerTcpBinding

Explanation:
Provides sessions and optionally provides ordered message delivery. This implemented session can cross SOAP and transport intermediaries.

http://msdn.microsoft.com/en-us/library/system.servicemodel.channels.reliablesessionbindingelement.aspx