I am looking for an opportunity to protect the items i used in my survey (like protection of copy, protection of print,...).

Thanks in advance!

There is no protection on the internet. To display something on the respondents screen it is already saved on their computer (temporarily) and can be accessed in the cache. So even if you put a script that for example disallows to right click on the page (to avoid copying text, etc), there is always the option to switch Javascript off. Or you simply make a screenshot.
So you might make it slightly more difficult for someone who has no idea how things work, but someone with half decent internet knowledge will know how to get around your little barriers.

In my opinion, it is not even worth the effort.

holch wrote: In my opinion, it is not even worth the effort.

I second that.
As a side note: The threadstarter mentioned a FAQ entry about protection in the German post of about this question.
www.rrz.uni-hamburg.de/services/software.../limesurvey/faq.html

The protection suggested there was to use CSS classes in every question you want to hide.

CSS classes:
noprint - No print via browser
nocopy - No copy of text
nodl - No download of pictures

Never seen that before. Might be a theme modification done by the Uni Hamburg.