Years ago, I was fascinated to learn that every language in the world has words for one, two and many. Moving on the count of three seems to be international and no more than three choices seems to be universal for children and older people with cognitive disabilities. The number three seems to be a magical, lucky number that is easy to understand. I have used three whenever a low number was needed for years, and it seems to work.
Preferences begin as yes or no, but within ACL 2.0, we can offer two or three choices that they can point to. Offering a choice is a lovely way of recognizing the person who is still here.