Which track best exemplifies the classic trap sound T.I. pioneered?

I don't think TIP innovated a sound as so much he created a subgenre and subject matter. A Trap is a very specific way of selling drugs and very specific to an area of the country. It's more a type of mentality and lingo. He gave a public name to something that already existed in Atlanta. I'd say TI signature sound is the sound he created with DJ Toomp which not many were able to replicate

I think Motivation, Why You Mad at Me, and Praying for Help are the pillars of this album