Quality is what matters, not quantity. After all, there’s no need to work with ten alternatives of CAD, if AutoCAD is the best one. Of course, you can prefer another program… But anyway, it makes no sense to talk about working with three or four products with the same functionality.
On the top of that, if you mention too many programs, recruiters can easily get a feeling that you are not persistent and aren’t very skilled with one software, but know a little of many. That would not be good. So, you should name some programs, but not too many. Focus on the advantages you saw while working with each program.
Practical tests may surprise you
It is better to be humble. They can let you work with CAD or Photoshop right in the interview. After all, it is the best way to see if you can really do your job in the program. Practical exercises are becoming pretty common in graphic design interviews, so be aware of it.
Recruiters use this question as a test of your trustworthiness too. If you say you are skilled with Photoshop, but are unable to complete the assigned tasks later, you will not get the job. They will not trust you anymore. Without trust, there is no job contract…
Therefor, I suggest you to be humble and name only programs you can really work with. You should say how long you have been working with it and list few advantages it has (you can add examples from the projects you completed). It is the best way how to answer this question.