ช่วยหน่อยครับ ทำหน้า แก้ไขข้อมูล อ่าน listmenu จากฐานข้อมูลได้ แต่กำหนด selected ค่าไม่ได้

<select name="education">
<option value=""><-- Please Select Item --></option>
<?
include '../include_file/config.php';
$strSQL = "SELECT * FROM education ORDER BY education_id ASC";
$objQuery = mysql_query($strSQL)or die ("Error Query [".$strSQL."]");
while($objResuut = mysql_fetch_array($objQuery))
{
if($strDefault == $objResuut["education_id"])
{
$sel = "selected";
}
else
{
$sel = "";
}
?>
<option value="<?=$objResuut["education_id"];?>" <?=$sel;?>><?=$objResuut["education"];?></option>
<?
}
?>
</select>

<?php
session_start();
	include'../include_file/config.php';
	$strSQL = "SELECT * FROM member WHERE username = '$username'";
	$objQuery = mysql_query($strSQL)or die("erroe=$	$strSQL");
	$objResult = mysql_fetch_array($objQuery);
	
	$str_birthday=$_POST['birth']; 
	$str_gender=$_POST['gender'];
	$str_nation=$_POST['nation'];
	$str_language=$_POST['lang'];
	$str_education=$_POST['education'];
	
	$sql_insert="UPDATE `nipontour`.`member` SET `gender` = '$str_gender',`nationality` = '$str_nation',`language` = '$str_language',`birth` = '$str_birthday',`education_id` = '$str_education' WHERE `member`.`username` ='{$_SESSION['username']}'";
	$sql_result=mysql_query($sql_insert)or die ("error=$sql_insert");
	mysql_close();
	echo"<script>window.location='../editprofile/p_profile.php';</script>";
?>