I have hundreds of choices that can be grouped into 8 categories for one question. Participants are supposed to multi-select several choices in the list. I chose to use a multi-select box so that participants can both select and enter the choices they want, but the feature of multi select box does not allow me to make an choice exclude (i.e., if participants chose "none," they can still select other choices). Additionally, as the list is too long, it tends to be biased to the choices at top of the list. Is it possible to make the choice groups clickable so that the question would show the choice groups at first (e.g., with a small "+" button behind to indicate it is expandable) and whenever they are clicked, it will expand to show corresponding choices in that specific group? Or does anyone have any innovative ideas to display these choices?

Use select2. Here is an example.

Organize hundreds of choices in a multi select box

Organize hundreds of choices in a multi select box | Experience Community