单项选择题 You are developing a Windows Communication Foundation (WCF) service. The following code defines and implements the service. (Line numbers are included for reference only.) 01 [ServiceContract(SessionMode = SessionMode.Allowed)] 02 public interface ICatchAll 03 { 04 [OperationContract(IsOneWay = false, Action = "*", ReplyAction = "*")] 05 Message ProcessMessage(Message message); 06 } 07 08 public class CatchAllService : ICatchAll 09 { 10 public Message ProcessMessage(Message message) 11 { 12 13 ... 14 return returnMsg; 15 } 16 }You need to ensure that two identical copies of the received message are created in the service. Which code segment should you insert at line 12?（）

单项选择题 You are developing a Windows Communication Foundation (WCF) service. One of the parameters used with the service operations is a security token. The security token is not sensitive. The monitoring software tracks security tokens and can read tokens in clear text only.The company security policy requires that you validate all clear text data passed over the corporate network.You need to ensure that the service verifies that the security token is not changed during transit. What should you do?（）

单项选择题 You develop a Windows Communication Foundation (WCF) service that uses basic authentication for client credentials. This service is currently configured to use message security. The service is hosted on a server in workgroup mode.Users report that their passwords are stolen when they use public computers.You need to ensure that messages are secure and users are authenticated.You prevent the service from being called over HTTP through Microsoft Internet Information Services (IIS) configuration. What should you do next?（）