问题：

[单选]

You are creating a Windows Forms application by using the .Net Framework 3.5.You create an instance of a Backgroundworker component named backgroundWorker1 to process operations that take a long time.You discover that when the application attempts to report the progress，you receive a System.InvalidOperationException exception when executing  thebackgroundWorker1.ReportProgress method.You need to configure the BackgroundWorker component appropriately to prevent the application from generating exceptions.   
What should yo do？（）

A . Set the Result property of the DoWorkEventArgs instance to True before you attempt to report the progress.
B . Set the CancellationPending property of backgroundWorker1 to True before you attempt to report the background process
C . Set the WorkerReportsProgress property of backgroundWorker1 to True before you attempt to report the background process.
D . Report the progress of the background process in the backgroundWorker1_ProgressChanged event.