There is still a category Quizzing under Preferences. However some of the preferences have been moved to the Properties panel of the Results slide: Attempts on quiz level, Pass/Fail actions etc... They used to be in the Quizzing Preferences under Pass/Fail.
However you can build a 'Quiz' by using only scored objects (formerly labeled as Custom questions). In that case the Results slide is NOT added automatically and you don't have access to its Properties. It would be better to move Pass/Fail again to Quiz Preferences.