Answer: D) A hand comes out of the lake to grab King Arthur’s sword.
Explanation: A supernatural event is a situation or a thing that can't be explained by nature or science, and are assumed to originate from otherworldly forces. From the given situations from "Morte d'Arthur by Sir Thomas Malory", the one that represents an example of a supernatural event is the corresponding to option D: A hand comes out of the lake to grab King Arthur’s sword, because it seems that it doesn't have a logical explanation in nature or science.
The best possible answer would seem to be C.
He feels sad and moody for disobeying Atticus
I would imagine the reader would feel anxious, especially to know what would happen next. It's a turn of events that will leave you on the edge of your seat.