1
Reason: Quotes are used in between quotes in american and british writing.
It's a conflict of interest. Where on one hand she knows what she should do and on the other there's something that she wants. Since there's the option for own personal gains with the two, it's conflict of interest.
Answer:
The oxygen bottles reveal that the climb up Mount Everest is so difficult that climbers cannot carry their equipment back down the mountain.
Explanation:
The partially used bottles imply that climbers can reach high altitudes without the use of oxygen.