Create a board game with pop ups

Further to my engineering course, discussed this idea with the client and they liked  I'm it. The idea is a board game which I'm sure many of you have done before but I'm unsure how. 

So, the idea is to have a flat board with images of the injection machine parts. They click on the parts to show if they can identify them or not. I know how to get the question up but I don't know how to create the triggers that show whether they are correct or not. Can someone assist?

Thanks so much! See the idea below. Obviously the design is crude at this point. 

below.