Hey Scott,
I just did some playing around with this and think I have found out why thats happening.
When we are parsing through a data source to find the options to display, we will read the rows and then the columns. There is a good explanation here (it says Google Sheets but is also applicable to Excel): https://support.prontoforms.com/hc/en-us/articles/4406631466260-Troubleshooting-Google-Sheets-Data-Source-Multiselect-Question-Showing-Blanks
It describes how we process the records in a data source and explains why would see a blank value in your drop down. In my test, I have 2 columns that are used for my options. If these 2 columns have different number of options, you will generate a blank value in the list of options because ProntoForms needs to read that row to get the options for the other column and just assumes that "blank" is an option.
Example:
Data Source with different number of options:
The app:

Data source with the same number of options:


Hope this helps!
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Ian Chamberlain
Implementation Specialist
ProntoForms
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Original Message:
Sent: 05-09-2022 21:20
From: Scott Gilleland
Subject: Multi-select or Dropdown from Data Source question
When using a Multi-select or Dropdown with options from a data source, I get a blank selection choice at the bottom of the popup, like this:
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Scott Gilleland
Senior Field Service Engineer
Messer Cutting Systems
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