DataReader dr is a variable but is used like a method in C#

How to solve the problem ?

Error 2 'dr' is a 'variable' but is used like a 'method'

 protected void Page_Load(object sender, EventArgs e)
    {
        OleDbCommand cmd2 = new OleDbCommand("select Q,a1,a2,a3,a4 from ope", Con);
        Con.Open();
        OleDbDataReader dr = cmd2.ExecuteReader ();
        if (dr.Read())
        {
            Label2.Text = dr(0);
            RadioButton1.Text = dr(1);
            RadioButton2.Text = dr(2);
            RadioButton3.Text = dr(3);
            RadioButton4.Text = dr(4);
        }
       
        Con.Close();
    }