【单选题】你在创建一个名为Location.aspx的ASP.NET页面。Location.aspx包含一个显示国家下拉列表的
A、在CountyList.ascx的code-befind(代码隐藏)文件里增加下面一行代码: Protected TKCounty As DropDownList
B、在CountyList.ascx的code-befind(代码隐藏)文件里增加下面一行代码: Public TKCounty As DropDownList
C、在Location.aspx的code-befind(代码隐藏)文件里增加下面一行代码: Protected TKCounty As DropDownList
D、在Location.aspx的code-befind(代码隐藏)文件里增加下面一行代码: Public TKCounty As DropDownList