A Windows Communication Foundation (WCF) client uses the following service contract. (Line numbers are included for reference only.)
01 <ServiceContract()>
02 Public Interface IService
03
04 <OperationContract()>
05 Function Operation1() As String
06 <OperationContract()>
07 Function Operation2() As String
08
09 End Interface
You need to ensure that all calls to Operation1 and Operation2 from the client are encrypted and signed. What should you do?

A.
Set the ProtectionLevel property in line 01 to EncryptAndSign.

B.
Set the ProtectionLevel property in line 04 and line 06 to Sign.

C.
Add a SecurityCriticalAttribute for each operation.

D.
Add a SecuritySafeCriticalAttribute for each operation.