How to cite images and sounds and does is using public images/sounds frowned upon by the judges as compared to hand drawing/recording?

My playground currently uses images and sounds, but I'm not sure how to cite it. Do I just reference the URL link or does it need to be very formal, like using MLA 8 format? Also, does using public images and sounds deter my playground? My question is does using public images and sounds negatively impact my submission, since there is always the option to handdraw everything? My app is not focusing on visual storytelling (e.g. a storybook). Please answer my two questions above quickly, since I only have one day left!!!!

You may include third-party open source licensed code and/or public domain images and sounds, with credit and an explanation of why it was used.


How to cite images and sounds and does is using public images/sounds frowned upon by the judges as compared to hand drawing/recording?
 
 
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