正解は「
Notice: Undefined variable: pref_quiz in /var/www/html/quiz_result_2.php on line 204
Notice: Trying to access array offset on value of type null in /var/www/html/quiz_result_2.php on line 204
」
解説：
Notice: Undefined variable: pref_quiz in /var/www/html/quiz_result_2.php on line 204
Notice: Trying to access array offset on value of type null in /var/www/html/quiz_result_2.php on line 204
