Final answer:
The correct answer is B. The reaction of others when Theseus and Arthur retrieve the sword serves to increase tension in both stories.
Step-by-step explanation:
The correct answer is B. The reaction of others when Theseus and Arthur retrieve the sword serves to increase tension in both stories. This is because the reaction of others indicates the significance and stakes of the situation. It shows that the retrieval of the sword is not a simple task and adds an element of suspense and conflict to the stories.