Conditional action block

I wish to perform a If else condition check with mulitple conditions.

Logically it would be something like this:

If MyVariable == "A" OR MyVariable =="B" OR MyVariable == "C" OR MyVariable == "D"

<perform assignment1>

Else

<perform assignment2>

I know I can use conditional action block with multiple inputs. But is there a simple way to do this.

Appreciate any help on this.

Thanks