Create List Item using Microsoft Flow when multiselect field present

I’m trying to create a new list item when a document is created in specific folder using MS Flow. That part I can get it to work without any issues. But, now there is a field that’s a Choice field where I need to use Check boxes (allow multiselect).

This is what I’m doing: enter image description here

I’m not sure how to populate the Review Group field’s checkboxes. I also tried using array instead of string variable, and it didn’t work either.

Any ideas?