Authors can add custom feedback to quizzes within a course. Quiz feedback will display to users after they have submitted their answer to the quiz question.
Quiz feedback can be customized to display separate messages for correct and incorrect answers or the same message for any answer. The option to create different feedback for correct and incorrect responses is not available for Short Answer quizzes.
Open Author Menu
In the Global Navigation menu, click the Author icon. Then, click the Courses menu option.
Note: The Global Navigation menu may differ depending on what is enabled in your account.
Click the Edit icon.
To add a new quiz question, click the Add Question link . To open an existing question, click the name of the question .
Add your feedback for correct answers in the Correct field  and incorrect answers in the Incorrect field . If you do not enter your own feedback, feedback will display as the default messaging .
Note: This option is not available for Short Answer quizzes.
Show Same Feedback
To show the same feedback message for any answer, check the Show the same feedback for CORRECT and INCORRECT answer checkbox . Then add your feedback in the Feedback field .