Dynamic Dropdown Menu in Storyline 360

Hello,

We are currently working on creating a "Learner Profile" survey to gather some additional information about our learners. We would like to create some drop-down menus for "State", "County", and "Agency" in our current file.

We have 300+ agencies that we need to list in a drop-down selection. Instead, we are wondering if it's possible to host the list of agencies in a csv or text document somewhere (e.g., Box) and then have Storyline360 run some kind of script to allow them to make their selection.

Does this sound possible? Or is this just an over-ambitious idea?

I've attached our current .story file for reference. It currently just has placeholder boxes where I would like to build the drop-down menus.