单项选择题 Your company has a Windows Communication Foundation (WCF) service at the URL http://services.contoso.com/OrderLookupService.svc.The section of the configuration file is as follows. (Line numbers are included for reference only.)01 02 03 04 05 06 ...0708 09 10 11 You need to ensure that the service publishes the WSDL description at http://services.contoso.com/OrderLookupService.svc?wsdl. What should you do?（）

单项选择题 You are developing a Windows Communication Foundation (WCF) service. The service operation takes a customer number as the only argument and returns information about the customer. The service requires a security token in the header of the message. You need to create a message contract for the service. Which code segment should you use?（）

单项选择题 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?（）