Oh, yes, I see. I did not test thoroughly enough.
In that case, to allow for a "mandatory" setting, I would...
1) Insert a hidden (via CSS class) multiple choice question before the array with randomized sub-questions.
2) Add this script to the multiple-choice which will check the first 3 boxes:
Code:
<script type="text/javascript" charset="utf-8">
$(document).on('ready pjax:scriptcomplete',function(){
var thisQuestion = $('#question{QID}');
// Check first 3 options (but only if page has not been visited)
if($('input:checkbox:checked', thisQuestion).length == 0) {
$('input:checkbox:lt(3)', thisQuestion).each(function(i) {
$(this).prop('checked', true);
$(this).nextAll('input:hidden:eq(0)').val('Y');
checkconditions(this.value, this.name, this.type);
});
}
});
</script>
3) Place an array filter on the array so only rows checked in the hidden question will be shown (and relevant).
Sample survey attached:
