Multi language graded quizzing with question banks

Hello,

I have created Storyline 2 course with three sections organised as tabs.  At the end of this course, after user completes all the 3 sections, they need to access the 4th tab which is a quiz section.  As of now, the users can freely navigate to all these 4 tabs.  How can I make the Quiz tab available to learners only after they have completed 3 sections?  Sort of forcing and encouraging them to complete all the sections before processing to quiz section.  Here is a screen-shot of the interface.  Many thanks