Which code segment should you use?

You create a Windows Workflow Foundation application by using Microsoft .NET Framework 3.5. When a user logs in, the application uses the InvokeWebServiceActivity activity to retrieve data from a Web service. You need to retrieve the logged-in user details from a local database when the Web service is being called. Which code segment should you use?

A.
this.invokeWebServiceActivity1.Invoked += new
EventHandler<InvokeWebServiceEventArgs>(OnInvoked); void OnInvoked(object sender, InvokeWebServiceEventArgs e){ …}

B.
this.invokeWebServiceActivity1.Invoking += new
EventHandler<InvokeWebServiceEventArgs>(OnInvoking); void OnInvoking(object sender, InvokeWebServiceEventArgs e){ …}

C.
this.invokeWebServiceActivity1.StatusChanged += new
EventHandler<ActivityExecutionStatusChangedEventArgs> (OnStatusChanged); private void OnStatusChanged(object sender, EventArgs e){ if (invokeWebServiceActivity1.ExecutionStatus == ActivityExecutionStatus.Executing) { … }}

D.
this.invokeWebServiceActivity1.StatusChanged += new
EventHandler<ActivityExecutionStatusChangedEventArgs> (OnStatusChanged); private void OnStatusChanged(object sender, EventArgs e){ if (invokeWebServiceActivity1.ExecutionStatus == ActivityExecutionStatus.Compensating) { … }}