Answer:
A novel about two modern-day explorers seeking a missing treasure deep in the wooded mountains
Step-by-step explanation:
Harper enjoys mysteries and thrillers, so that marks out the drama about the young couple and the poetry written about nature (although it does talk about nature, which she likes, it does not have the thrill that she wants). However, she also does not enjoy sci-fi. This knocks out the short story about teenagers being abducted by aliens, even though it is about a camping trip. Now, there is only one left: the novel about the explorers seeking treasure in the mountains. It has the thrill that she desires, and it is set in the mountains. It is also at her reading level, as it is a novel as opposed to a short story. All in all, this is the text that I would recommend to Harper.