"Blank" answers shouldn't leave a blank slot in Single Select or Dropdown questions#223

Currently, if I use a variable as a possible answer to a Single Select or Dropdown question, but the variable is blank, then the Single Select and Dropdown make an entry for that answer but that slot is blank. If the answer is blank, it should NOT give it a slot in these types of questions.

Combobox questions do this correctly and “blank” answers are left out without any corresponding “blank” slot in the answer dropdown.