The dropdown is very similar to
Choice field. They are all for selection operation. However, Choice normally is rendered to
cross sign although its other option can include text. But dropdown is rendered to text to your PDF.
Value is invisible in form but it is the text of your PDF. In your form, the user only sees these
Labels. In most case, they could be same. But you also can make them different. For example, if you want to show countries in your dropdown, they are normally the full name of the countries. But in PDF, you may want to show the country code.