Windows Communication Foundation （WCF） application uses a data contract that has several data members. You need the application to throw a Serialization Exception if any of the data members are not present when a serialized instance of the data contract is deserialized. What should you do？（）

• A、 Add the Known Type attribute to the data contract.Set a default value in each of the data member declarations.
• B、 Add the Known Type attribute to the data contract.Set the Order property of each data member to unique integer value.
• C、 Set the Emit Default Value property of each data member to false.
• D、 Set the Is Required property of each data member to true.