第4题: [单项选择]Questions 19 to 22 are based on the conversation you have just heard. A. An alien spacecraft landing. B. The impact of a meteorite. C. A volcanic eruption. D. The blizzard conditions in Alaska. 参考答案:B 答案解析:[听力原文]19-22 M: Hello. This is Greg Rice reporting live in Barrow, Alaska. W: Hello, Greg. Is e