单项选择题 You create a Microsoft ASP.NET application by using the Microsoft .NET Framework version 3.5. You write the following code fragment：   <asp：DropDownList AutoPostBack="true" ID="DropDownList1" runat="server"   onselectedindexchanged= "DropDownList1_SelectedIndexChanged">   <asp：ListItem>1</asp：ListItem>   <asp：ListItem>2</asp：ListItem>   <asp：ListItem>3</asp：ListItem>   </asp：DropDownList>    You also add a MultiView control named MultiView1 to the Web page. MultiView1 has three child View controls.  You need to ensure that you can select the View controls by using the DropDownList1 DropDownList control. Which code segment should you use？（）

单项选择题 You create a Microsoft ASP.NET application by using the Microsoft .NET Framework version 3.5. You write the following code fragment：   <asp：ListBox SelectionMode="Multiple" ID="ListBox1" runat="server">  </asp：ListBox>   <asp：ListBox ID="ListBox2" runat="server">  </asp：ListBox>   <asp：Button ID="Button1" runat="server" Text="Button" onclick="Button1_Click" />    You need to ensure that when you click the Button1 control， a selected list of items move from the ListBox1 control to the ListBox2 control.  Which code segment should you use？（）

单项选择题 You create a Microsoft ASP.NET application by using the Microsoft .NET Framework version 3.5. You add an XmlDataSource control named XmlDataSource1 to the Web page. XmlDataSource1 is bound to an XML document with the following structure：   <？xml version="1.0" encoding="utf-8" ？>   <clients>   <client ID="1" Name="John Evans" />   <client ID="2" Name="Mike Miller"/>  ...  </clients>    You also write the following code segment in the code-behind file of the Web page：   protected void BulletedList1_Click （object sender， BulletedListEventArgs e） {   // ...   }    You need to add a BulletedList control named BulletedList1 to the Web page that is bound to XmlDataSource1.  Which code fragment should you use？（）