You can go so many different directions here.
I think Smells Like Teen Spirit is the immediate go-to
However, that is completely ignoring hip-hop, R&B, and gangster rap which exploded in the 90s.
The answer very well might be Regulate by Warren G and Nate Dogg
It Was A Good Day - Ice Cube
The Crossroads by BONE?
Foo Fighters - Everlong (this is my lowkey favorite answer)
But if we are being honest It's All About the Benjamins by Puff Daddy is kind of perfect for multiple reasons.
And how can we not mention "I Swear"?