dynamic dropdown with text divider?

Hi all,
I need to add a text divider between options in a dynamic dropdown menu.

I would like to obtain something similar to this dropdown:

CATEGORY 1
- option 1
- option 2
- option 3
CATEGORY 2
- option 4
- option 5
- option 6

where CATEGORY 1 and CATEGORY 2 are not selectable.
I can do this with static content, but I don't know how to do this with dynamic content.
How can I do this with data bridge and dynamic data?

TIA
tony

The non-selectable options can use the <optgroup> tag instead of the <option> tag. It can probably be done most easily by nesting repeated regions with two recordsets. The first recordset would have the Categories table and would wrap around the <optgroup> tag. The second recordset would nest inside the first repeated region and filter based on the category to show the underlying products and it would have a repeat around the <option> tags.