Is there a way to hide the "no answer" option on some questions, while having it show on others? Most of the questions types I'm using are Array (5 point) and List (radio).

Thanks!

Change it to "mandatory".

But in my opinion it's always better to define your own scales instead of choosing the predefined "5-point-scale".
Here you are able to choose if there is a "N/A" or not.

Joffm

This is a general setting for non mandatory questions. You can switch that off and than add your own "no answer", just like Joffm suggested.