You have an existing Windows Communication Foundation (WCF) service that exposes a service contract over HTTP. You need to expose that contract over HTTP and TCP. What should you do?（）
Add a net.tcp base address to the host.
B. Add an endpoint configured with a netTcpBinding.
C. Add an endpoint behavior named netTcpBehavior to the existing endpoint.
D. Add a binding configuration to the existing endpoint named netTcpBinding.
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