You are developing a client application that consumes a Windows Communication Foundation (WCF) service. You use the svcutil.exe utility to create a proxy for the service. You use the svcutil.exe switches that generate asynchronous calls. GetFlight is a service operation that takes no parameters and returns a string. The GetFlightCallback method must be called when the service operation returns.You create an instance of the client proxy with the following code:var client = new TranvelServiceClient();You need to ensure that a callback is received when the GetFlight operation is called asynchronously.
Which code segment should you use?（）

You are developing a client application that uses the following code to consume a Windows Communication Foundation (WCF) service.(Line numbers are included for reference only.)
01 BasicHttpBinding myBinding = new BasicHttpBinding();
02 EndpointAddress myEndpointAddress = new EndpointAddress("http://contoso.com/TaxService.svc");
03 ...
04 ITaxService client = channelFactory.CreateChannel();
05 string data = client.GetData(1);
You need to consume the service.
Which code segment should you insert at line 03?（）