F: Would you please tell me something about your best holiday, Jason? ,M: Well, it was my trip to Nepal. We went there 10 years ago, walking in the mountains for 20 days. ,F: That's a long time. How far did you walk everyday? ,M: 15 kilometers or so. We had to climb up and down a lot everyday. At times, it was hard to walk as the air there was very thin and we had a lots of problems breathing, which made me anxious and depressed.
(A) F: I’m sorry, I didn’t understand. Could you repeat a little louder, please? (B) F: Oh! No! How can they left you in the ocean all by yourself! (C) F: I knew. the polluted aire there did harm to your breathing systom. (D) F: Yes, the thin air there made it difficult to breath sometimes.
D