You're not going to be able to sort them with the way that you currently have this setup. The only way you would be able to sort them is if you have a relationship between the Classes and Feedback tables, where Classes is the Parent. I would then suggest using the Name or Date or some combination of those as the Proxy for the relationship so that this would then be the drop-down you would use, instead of a Multiple-Choice field.
Once you have this setup, you can change how the drop-down works in the Elements properties on the form editor and select the report you would like to base the drop-down on. The drop-down would then use any sorting / filtering settings you've setup for the presentation of the choices in the drop-down.
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Blake Harrison - DataBlender.io
Quick Base Solution Provider
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