Wikimedia Bugzilla is closed!

Questions, the answers of which are of no concern to the purpose
of a questionaire are illegal and must not be asked at all here.
If they are asked, you are free to not answer them or supply
random wrong answers.

There are lots of personal questions, such as the living
circumstances, income, age, education, current work, marital
status, language, sex, internet use, and so on.

There are also questions to which one may not have an answer,
possibly not even a useful estimate, such as number of
contributions to Wikipedia (which one(s), btw?)

You must provide a choice "no answer", "unknown", or better both,
for those questions. Not only because you are legally obligued, but
also because you cannot get useful or reliable results otherwise.