Answer:
A) It makes the narrator appear uneducated.
Step-by-step explanation:
Mark Twain intentionally uses double negatives to give more colour to the story and the writting, Mark Twain used to wrote a lot in a journalistic way with narrative writting and adding the style of talking and direct speaking form the people helped to give more context and to make it feel more close and more empathic with the reader, in this case Mark Twain uses the double negatives to show the uneducated background of the narrator.