Certkiller.com has employed you as a system administrator. You make sue of .NET Frameworkv3.5 to create an ASP.NET application. The application contains a Web form file. This file isnamed MovieReviews.aspx.  The file is linked to a LinqDataSource DataSource named LinqDataSource1. LinqDataSource1contains a primary key named TestMovieID. The application also contains a DetailsView controlthat is named CKDetailsView. The code below is included in the MovieReviews.aspx file. （The linenumbers is included for reference purposes） 01  05  06   09   11   13   15  16   All Certkiller clients makes use of DView1. To ensure productivity you need to make sure that theyare able to insert and update content in the control. It is vital that you ensure the prevention ofduplivcation of the link button controls for the Edit and New operations. You thus need todetermine the appropriate code fragment you need to insert at line 3.  What should you do？（）

• A、A
• B、B
• C、C
• D、D