stuck between 2 & 4. I answered 2, but I'm guessing that I was wrong.

Answer:
Second one
Explanation:
Trepidation means worry. This word suits perfectly the situation the hiker is in.
Surmount means overcome. The hiker's friends helped her to overcome that feeling of worry.
Hi there!
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I'm not really sure if my answer will be right but, I would go the the second one, because she has to overcome her fear, right?
Surmount : overcome (a difficulty or obstacle).
Hope this helped you!