You create a Microsoft ASP.NET application by using the Microsoft .NET Framework version 3.5. You create a Web form by using ASP.NET AJAX. 
You write the following client-script code fragment to handle the exceptions thrown from asynchronous postbacks：  
01 <script type="text/javascript">  
02   function pageLoad（）  
03   {  
04     var pageMgr = 
05       Sys.WebForms.PageRequestManager.getInstance（）；  
06 ► 
07   }  
08  
09   function errorHandler（sender， args）  
10   {  
11 ► 
12   }  
13 </script>
You need to ensure that the application performs the following tasks： 
use a common client-script function named errorHandler. 
udpdate a Label control that has an ID named lblError with the error message. 
prevent the browser from displaying any message box or Javascript error.  
What should you do？（）

A.A
B.B
C.C
D.D