You are developing a Windows Communication Foundation (WCF) service that does not
operate on a duplex channel. You find that operations do not start until all previous
operations have finished. The service hosting code contains the following lines. Dim service
= New WarehouseService() Dim hose = New ServiceHost(service) You need to ensure that
new operations do not wait for previous operations to finish. Which attribute should you use
to decorate the service?

A.
<ServiceBehavior( InstanceContextMode:=InstanceContextMode.Single,
ConcurrencyMode:=ConcurrencyMode.Single) >

B.
<CallbackBehavior( ConcurrencyMode:=ConcurrencyMode.Multiple)>

C.
<ServiceBehavior( InstanceContextMode:=InstanceContextMode.Single,
ConcurrencyMode:=ConcurrencyMode.Reentrant)>

D.
<ServiceBehovior( InstanceContextMode:=InstanceContextMode.Single,
ConcurrencyMode:=ConcurrencyMode.Multiple)>