Radio Button options don't appear in correct order

I have several fields of type Radio_button, each with values "Yes", "No" and "N/A." For all of these fields, the values show up in the order that I entered them. One of the fields, however, refuses to show up in the correct order, even though it's set up in exactly the same way as the others. I tried deleting the field options and re-entering them, but they remain in the wrong order: "No" "Yes" "N/A".

I had to create an entirely new field to replace the wonky one, and the new field works fine, but I'm reporting the bug anyway.