A Windows Communication Foundation (WCF) service is deployed with netTcpBinding.
This service uses a duplex message exchange pattern.You are developing the next version of the WCF service.
You discover that your company’s hardware load balancer performs correctly only for WCF services that use HTTP.
You need to ensure that your service works with the load balancer. What should you do?

A.
Use basicHttpBinding.

B.
Create a custom binding that has the compositeDuplex, textMessageEncoding,
and namedPipeTransport binding elements in this order.

C.
Create a custom binding that has the compositeDuplex, textMessageEncoding,
and wsHttpTransport binding elements in this order.

D.
Use wsHttpBinding.

Explanation:
Custom Bindings
You can add binding elements by adding the desired BindingElement objects to its Elements collection.
The order in which the binding element is added is very important. The order of adding the binding elements is as follows:
1. Transaction Flow (not required)
2. Reliable Messaging (not required)
3. Message Security (not required)
4. Composite Duplex (not required)
5. Message Encoding (required)
6. Transport Security (not required)
7. Transport (required)

Bindings
(http://msdn.microsoft.com/en-us/library/ff650874.aspx)

WCF Bindings in Depth
(http://msdn.microsoft.com/en-us/magazine/cc163394.aspx)