<span>The lines from "Mending Wall" that best indicate that the speaker is amused while repairing the wall are these ones: We have to use a spell to make them balance: / "Stay where you are until our backs are turned!" This sentence shows the playfulness in the narrator's voice, as opposed to other lines that are far more serious. The speaker finds something quite amusing which is why he utters these lines. His repairing of the wall is being distracted by the events around him that seem to interest him more.</span>
I believe that the answer is either C, or D. They both seem plausible.
Maybe try zooming in a little more :)
