Minor edit to quiz.php

git-svn-id: https://plugins.svn.wordpress.org/quiz-master-next/trunk@870972 b8457f37-d9ea-0310-8a92-e5e31aec5664
Minor edit to quiz.php

git-svn-id: https://plugins.svn.wordpress.org/quiz-master-next/trunk@870973 b8457f37-d9ea-0310-8a92-e5e31aec5664