I would like to repopulate a drop down field from a google spreadsheet.

I would like to repopulate a drop down field from a google spreadsheet. The form would need to get 20 or so single names into a single name Drop Down field, our therapist then would chose the client from the drop down for billing. The google sheet is filtered and sorted.

I'm sorry, but this is not possible. We have the spreadsheet to form widget. 

https://www.jotform.com/help/442-How-to-Use-the-Spreadsheet-to-Form-Widget.

Please check. I hope this will work for you.