Drop Down Menus and Text Blocks

I am doing a trial of the software and I'm stumped by something that should be relatively easy to do. I put a drop-down menu on a screen with 3 items on it. When the user select an item, I want text (different text for each item) to populate a single text block (the text would be replaced as each item is chosen). I've poured over the help information for over an hour and can't figure out how to make this happen. Can anyone help?

Discussions have been disabled for this post