The main questions I would have in any case have nothing to do with what your field looks like or what your code looks like.
1) How is the content for these fields being added? Is all of the content being added by actually editing the posts in the admin? Or, is there some type of import process being used to add the content?
2) Assuming that by drop down you mean a select field, does this field allow multiple selections or only one selection?
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