I used almost all of the answers posted here but not comfortable with that so i dig one step furter and found easy solution that fits my need and feel worth sharing with you guys.
Instead of iteration all over the options or using JQuery you can do using core JS in simple steps:
Example
<select id="org_list">
<option value="23">IBM</option>
<option value="33">DELL</option>
<option value="25">SONY</option>
<option value="29">HP</option>
</select>
So you must know the value of the option to select.
function selectOrganization(id){
org_list=document.getElementById('org_list');
org_list.selectedIndex=org_list.querySelector('option[value="'+id+'"]').index;
}
How to Use?
selectOrganization(25); //this will select SONY from option List
Your comments are welcome. :) AzmatHunzai.