24. Which of the following best describes the reaction of scientists?
(A) They quickly identified the cause and provided a clear explanation.
(B) They dismissed it as an illusion and did not proceed any further investigation.
(C) They were puzzled and launched investigations, but found no clear answers.
(D) They eventually confirmed that it was caused by a volcanic eruption underwater.

20. (A) repair (B) impair (C) expand (D) dispatch

21. (A) displays (B) scenarios (C) revelations (D) combustions

22. (A) adept (B) elevated (C) infused (D) outbound 

23. What was the most unusual feature of the “Sky River”? (A) It was a glowing body of water suspended mid-air in the sky. (B) It was a cloud formation with mist and frost mistaken for a river. (C) It was a rare form of high-altitude rainstorm with flood and mudflow. (D) It was a mirage caused by light refraction from the highly industrialized society.

25. What did eyewitnesses report seeing inside the Sky River? (A) Wreckage of sunken ships floating mid-air. (B) A whirlpool leading swiftly into another dimension. (C) Icebergs and glaciers melting rapidly under the air pressure. (D) Fish and marine animals suspended as if underwater.

26. Which of the following theories was NOT mentioned in the passage as a possible explanation for the event? (A) A gravitational rupture. (B) An alien intervention. (C) A massive optical illusion. (D) A connection to an alternate dimension.

27. What was the ultimate fate of the Sky River? (A) It evaporated gradually over a period of weeks. (B) It disappeared suddenly without leaving any trace. (C) It descended to the ocean and merged with the sea again. (D) It appears periodically in the sky as a new geographical feature. 

28. Which of the following would be the most appropriate title for this passage? (A) AI vs. Students: The Ultimate Classroom Experiment (B) The Disappearance of Human Professors in Academia (C) The Challenges and Threats of Traditional Universities (D) AI Professors: Revolutionizing or Undermining Education

29. What is the primary focus of the passage? (A) The emotional responses of students to artificial intelligence in education. (B) The achievements and ethical implications of using AI in scientific research. (C) The technological advancements in natural language processing and calculation. (D) The implementation of AI technology and the debate over its impact on education.

30. According to the passage, what was the reaction of students upon discovering they had been taught by AI professors? (A) They were unanimously enthusiastic about the efficiency of AI educators. (B) Most students expressed deep concern about the future of human professors. (C) Reactions varied, with some students feeling amazed and others feeling deceived. (D) They strongly demanded refunds for tuition fees and compensation for their rights.