Directions: In this section, you will hear some news reports. At the end of each news report, you will hear some questions. Both the news and the question will be spoken only once. After each question, Choose the best answer from the four choices marked A, B, C, and D.Questions 2 to 3 are based on the passages you have just heard.[音频]2. listen to the recording
A. . The gradual collapse of abandoned gold mines.
B. . The overexploitation of underground water.
C. . The quick disappearance of forests and wetlands.
D. . The erosion of soil by floods and strong winds.