What distinguishing feature of realist literature does Mark Twain use in this excerpt from The Adventures of Huckleberry Finn?

I ain' gwyne to len' no mo' money 'dout I see security. Boun' to git yo' money back a hund'd times, de preacher says! Ef I could git de ten cents back, I'd call it squah, en be glad er de chanst.

dramatic dialogue
dialect
an unreliable character
setting
undecipherable language