How to limit options in a <select> based on another option selection

Question

I\'m trying to limit the number of options based on another selection. For instance in this example \"How many credits is the class you skipped?\" should be limited to equal

Answer 1

On change of your dropdown fire a onchange trigger and on the basis of values make the 2nd dropdown enable or disabled.

$("#semester_credits").change(function () {
        var $this=this;
        $("#skipped_total_credits").children().each(function(){
            $(this).attr("disabled",parseInt($this.value) < parseInt(this.value));
        });
    });

Check the fiddle here

EDIT

$this.value contains the value selected from "semester_credits" dropdown, now For each child of "skipped_total_credits", I am checking if that value is less than the children value then make it disabled, i.e attr("disabled", true) else make that children enabled.