Efficient Use of Sound Effects

Hello,

I have a question about the best practices for repeatedly using the same sound effects over and over.  I am designing a quiz game that will consist of > 50 questions.  I want a positive/happy sound effect to play when the viewer gets the correct answer and a negative sound effect to play when the viewer gets the answer wrong.  I want to display these questions randomly so I will likely be using a question bank.  

I have heard that every time you import a sound effect onto a slide it adds to the ultimate file size of the storyline product.  Is there a way I can import these sounds once but use them repeatedly for multiple slides?  I think you can do this using slide layers but then I won't be able to randomize my questions using a question bank.  Maybe I could import them to the master slide to cut-down on the ultimate file size that way? 

Thanks very much in advance for any help you can provide.

Brian Gibbens, Ph.D.