How to remove/hide select options from select-list

Answer 1

using css to hide options is not supported in IE, so you need to update the options list itself.

Try something like

$('#selectlist option[value=4]').remove();

Demo: Fiddle

or if you want to enable it later

var sel = $('#selectlist');
var opts = sel.find('option');

$(':checkbox').click(function(){
    sel.empty().append(this.checked ? opts : opts.filter('[value!=4]'));
}).click()

Demo: Fiddle