*WIP Feel free to edit*
Firstly, let's get one thing out of the way: sharks do not roar. They cannot roar and no shark has ever roared.
They not only lack vocal chords, but they lack lungs, making sharks a truly silent species.
Less well known, however, is that the "Roaring Shark" originates from the original film, Jaws.
The roaring of Vengeance originates from Tom and Jerry here. https://www.youtube.com/watch?v=TpDWXQmT_84