C. Necessary is the answer
Answer: I believe it would be letter (b)
Explanation: I had to answer this question yesterday and I am pretty sure this is the answer. Because it asks ¨the narrator gives an example of why oxygen is vital to climbers on Mt. Everest. How does the narrator develop this concept in the rest of the narrative?¨ so this is really the only plausible answer regarding the question.
Answer: C. The narrator discovers that the town holds an ancient curse.
Explanation: