jQuery appendTo（），json无法在IE 6,7,8中运行

I've been racking my head for two days trying to find a solution for this. I'm using jQuery.ajax() to grab values from the database to update a box when another box is changed. The php script grabs the values from the database and then spits out json. IT works fine in FF but in all versions of IE the select box doesn't get updated. I've confirmed that the json being output is good.I've been racking my head for two days trying t