Storyline 360 Pick Many Hotspot - How to ensure a set amount of hotspots (not all) are identified before allowing user to move on

Hi,

I've created a multiple (10 areas) hotspot question using 'pick many'. I now want to set the question up so that the user can find any 3 to move on. Can anyone share workarounds?

I can get the 3 answers with the numerical variable (i.e. each answer is worth 1 point and the variable can only move on once 3 or greater is achieved).

However, I'm not sure how to make sure this gets graded. i.e. any 3 answers can be marked as correct in results.

Thanks!