How to "fact check" with conditional formatting?

I'm sure it is a simple formula I'm missing, but I'd like to basically "fact check" in excel, using a formula and from there conditional formatting. Basically I have a type of schedule, and I want to make sure each column has at least 1 of certain text in it (to make sure all shifts are covered). So basically as long as Column A contains at least one instance of "A,B,C,D" etc, it is "True", and if not, false.

Is there a way to do this?