C# - Modify Page_load Method For Radiobuttonlist?

I have a page with radio buttons and a textarea that populates data dynamically based on your selection. The radio buttons act as a list of article titles and on selection you see the content of the article.

Within my pageload method, I want to allow users to be able to see a URL in their browser that points to value they've. That way they can link to the article within another source.

Currently, the method I have allows me to link to the button selection if I manually type in the following example URLs:

[URL]

[URL]

I'd like to modify this so that the URL appears in the browser when a radio button selection is made. Plus, on page load defaults to the "0" index if no value parameter was specified.

protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
int selected;
if (int.TryParse(Request.QueryString["selected"], out selected))
RadioButtonList1.SelectedIndex = selected;
RadioButtonList1.DataBind();
}
}
protected void RadioButtonList1_SelectedIndexChanged(object sender, EventArgs e)
{
string strRedirect;
strRedirect = "frm_Articles.aspx?selected=" + RadioButtonList1.SelectedIndex;
Response.Redirect(strRedirect);
}