There could be multiple correct answers to this excerpt from Thomas Malory's work on King Arthur. However, we have got a multiple choice question and we have to obtain the correct answer from these options. It is a supernatural event that has been described in this excerpt. And we don't observe first, second or fourth options in the excerpt. There are lines "...there came an arm and a hand above the water and took it and clutched it, and shook it thrice..." which is the paraphrase for the answer in the second option - An arm appears out of the water and shakes the sword three times. Therefore, the correct answer is the second one.