A WCF service code is implemented as follows. (Line numbers are included for reference
only.) 01 [ServiceContract] 02 [ServiceBehavior(InstanceContextMode = 03
InstanceConcextMode.Single)] 04 public class CalculatorService 05 { 06
[OperacionContract] 07 public double Calculate(double opl, string op, double op2) 08 { …
24 } 25 } You need to decrease the response time of the service. What are two possible
ways to achieve this goal? (Each correct answer presents a complete solution. Choose
two.)

A.
Change the service behavior to the following. [ServiceBehavior( InstanceContextMode =
InstanceContextMode.Single, ConcurrencyMode = ConcurrencyMode.Multiple) ]

B.
Change the service behavior to the following. [ServiceBehavior(InstanceContextMode =
InstanceContextMode.PerCall) ]

C.
Require the clients use threads, the Parallel Task Library, or other mechanism to issue
service calls in parallel.

D.
Require the clients to use async operations when calling the service.