As Trey has said, you can bind an option group to a character field. But what I often do is store the entire caption in that field instead of the first character. In cases where the captions for the choices are fairly short, this works well, otherwise, I do some kind of translation in code.

Note: This only works if your program only runs in one language. I have an app that runs in multiple languages, so the captions change. In that case, I bind the option group to a numeric field and do the translation in code, otherwise, it's difficult to code a case statement based on the value of the field. (Although, I've since come up with a scheme that will handle it.)