Going back to base layer after being in another layer

Hi, I am working on a training where the user will click on objects, and it will take them to another layer. From layer 1(2,3,4) I want the user to click a "learn more" button that would take them back to the base layer, so they can choose another object that will take them to layer 2 (3,4). How do I return to the base layer? I don't see that option under the trigger menu. 

Help? 

Thanks.