AerolineaFrba.Compra.Form6.comboBox2_SelectedIndexChanged C# (CSharp) Method

        private void comboBox2_SelectedIndexChanged(object sender, EventArgs e)
        {
            cboCuotas.Items.Clear();
               SqlDataReader varCuotas;
               SqlCommand consulta = new SqlCommand();
               consulta.CommandType = CommandType.Text;
               consulta.CommandText = "SELECT TC.CUO_NUM FROM [ABSTRACCIONX4].TIPOS_CUOTAS TC JOIN [ABSTRACCIONX4].TIPOS_TARJETAS TT ON TC.TIPOTARJ_COD = TT.TIPOTARJ_COD WHERE TIPOTARJ_DESC='" + cboTipoTarjeta.SelectedItem.ToString() + "'";
               consulta.Connection = Program.conexion();
               varCuotas = consulta.ExecuteReader();

               while (varCuotas.Read())
            {
                this.cboCuotas.Items.Add(varCuotas.GetValue(0));
            }
        }