You create a Microsoft ASP.NET application by using the Microsoft .NET Framework version 3.5. You create a custom Web user control named SharedControl. The control will be compiled as a library. 
You write the following code segment for the SharedControl control：
01 protected override void OnInit（EventArgs e）  
02 {  
03   base.OnInit（e）；  
04 ► 
05 }   
All the master pages in the ASP.NET application contain the following directive. <%@ Master Language="C#" EnableViewState="false" %>   
You need to ensure that the state of the SharedControl control can persist on the pages that reference a master page. 
Which code segment should you insert at line 04？（）

A.Page.RegisterRequiresPostBack(this); 
B.Page.RegisterRequiresControlState(this); 
C.Page.UnregisterRequiresControlState(this); 
D.Page.RegisterStartupScript("SharedControl","server");