听力原文：M: Did you hear about the air crash that occurred in South America recently？ It w

W: No, I didn't see anything in the news about it. What happened？

M: A foreign airliner was attempting to land at night in a mountainous area in Argentina and flew into a hill!

W: That sounds really terrible! Did anyone survive？

M: No, everyone aboard, including the crew, was killed instantly.

W: What were the circumstances？ Were they bad weather, a fire, or engine failure？

M: Apparently, there were some low clouds in the area, but mostly it was just miscommunication between the pilots and the air traffic controllers.

W: Weren't they both speaking in English, the official international aviation language？

M: Yes they were, but the transition from poor quality radios was slightly distorted and the accents of the Spanish speaking controllers was so strong that the pilots misunderstood a vital instruction.

W: How could a misunderstanding like that cause such a serious accident？

M: The pilots were told to descend to 22, 000 feet. The instruction actually meant22, 000 feet, but they thought they heard descend 2, 000 feet. That's a huge difference, and it should have been confirmed, but it was not. Unfortunately, the terrain of the mountains in Norweija ascend to 2, 000 feet.

W: So the pilots did descend to the wrong altitude then, because they were following the air controller's instructions.

M: Sadly enough, yes they did. It was a really bad mistake. Many people died as a result of the simply misunderstanding.

W: Wow, that's a powerful lesson on how important it can be to accurately communicate with each other.

What was the cause of the tragedy？

A．Bad weather.

B．Human error.

C．Breakdown of the engines.

D．Communications system failure.