Option Execute JavaScript will give you opportunity to run JavaScript code when a user answers all questions of the quiz. 

To modify JavaScript, click the Customize button in the Properties ->Result -> Reporting area.

The JavaScript Editor window will open.

You can insert quiz variables in Insert Variable drop-down and set Target to define script execution area. 

VariableDescription
PASSING_SCOREQuiz passing score (for graded quizzes only).
AWARDED_SCOREUser score for the quiz (for graded quizzes only).
PASSING_PERCENTQuiz passing percent is a number from 1 to 100.
AWARDED_PERCENTUser score for the quiz in percent of total. Percent is a number from 1 to 100.
QUIZ_STATUSStatus of the quiz: "Passed", "Failed", "Completed".
QUIZ_DURATIONTime in seconds spent by the user to pass the quiz.

Note: Quiz variable must be surrounded by "%" characters. Otherwise it will be defined as a string.