How can I make no selection the correct answer on a pick many interaction?

hi there, 

I have several pick many question slides and on one of them, the correct answer is not to tick any of the options. However, that doesn't seem to be possible because when I preview and try to submit, it keeps coming up with the 'invalid answer' box. Is there any way to make no ticks the correct answer (ideally without having to create a completely custom slide as I need to get this out by tomorrow ;-))?

3 Replies
David Read

Wow, hadn't though of doing it that way, that's so clever! I amended your idea slightly by creating another answer with a tick box and hiding it behind another answer so it wasn't visible. When the timeline starts, I have that object automatically ticked so that when they submit that is the correct answer but it's not visible for them. 

Thanks so much for your input, would never have thought about using hidden objects to achieve this!