The excellent Quiz engine works well.
For multiple choice, I want to give only points, if the question is answered 100% correct.
1) No correct answer missing.
2) no wrong answer selected.
I know that this can be solved with single choice and rewritten answers - but may be there is an option
to tell moodle to judge answers in an "all or nothing" way.
(There was a discussion about it - but I am not able to find it. The search finds always all forums - not only Quiz - regardless what I select)