The correct answer is B.
Using indirect dialogue allows Twain to compress and shorten the conversation. By using fewer words (instead of including the exact dialogue), Twain can keep the scene short and move on to a more interesting part of the story.
If the dialogue were written out exactly as it was spoken, it would take a lot longer to read, since many animals are speaking to the donkey in this scene.
A: here sits the proud winner of the contest
