ListItem with similar value - DropDownList

I am having a problem in getting the Text of DropDownList.SelectedItem.Text when there are more than one ListItem having the same "value"...It always selects the very first ListItem amoung those having same values..

Here is an exmaple:

 

  protected void Page_Load(object sender, EventArgs e)
{
for (int i = 0; i < 10; i++)
{
if (i == 2 || i == 8)
dpC.Items.Add(new ListItem(i.ToString(), "200"));
else
dpC.Items.Add(new ListItem(i.ToString(), i.ToString()));
}
}

protected void btn_Click(object sender, EventArgs e)
{
R ...