Quiz

The answer seems to be 'not easily', since that message is output at the same time as the Time limit: 20 mins message, and there is no easy way to tell them apart. (If things where done differently, a simple optoin would be to add the CSS like .mod_quiz_grading_method { display: none; } but there is no class name like that.

The easiest way to do this is to comment out this line of code: https://github.com/moodle/moodle/blob/1a727e121ef94ae80dd2a8a13f49049d3bc25ef3/mod/quiz/view.php#L181 . Of course, there are all the issues with editing Moodle core code that you should think about before you do it.