Questions 22 to 25 are based on the passage you have just heard.

Directions:In this section, you will hear three passages. At the end of each passage, you will hear three or four questions. Both the passage and the questions will be spoken only once. After you hear a question, you must choose the best answer from the four choices marked A, B, C and D). Then mark the corresponding letter on Answer Sheet 1 with a single line through the centre.

  • A Population explosion.
  • B Chronic hunger.
  • C Extinction of rare species.
  • D Environmental deterioration.
  • A They contribute to overpopulation.
  • B About half of them are unintended.
  • C They have been brought under control.
  • D The majority of them tend to end halfway.
  • A It is essential to the wellbeing of all species on earth.
  • B It is becoming a subject of interdisciplinary research.
  • C It is neglected in many of the developing countries.
  • D It is beginning to attract postgraduates’ attention.