Passage Two
[29]Do you have a tough math test coming up? Then listen to some classical piano music just before the test. You might end up with a higher score.Researchers at a university in California conducted an experiment. They asked a group of college students to listen to some piano music by a famous 18th century composer before taking a math test. They were surprised to find that the students' scores jumped 8 to 9 points. [30]The music seems to excite nerve activities in the brain similar to the activity that occurs when a person is figuring out a math problem. However, the scientists warn that before you get too excited about applying this method to your math test, [31]you should remember that brain-exciting effects last only 10 to 15 minutes. Would rock music work as well as the piano music did? No, the scientists say. In fact, the less complex music might even interfere with the brain's reasoning ability.

Questions 29 to 31 are based on the passage you have just heard.
29. What is this passage mainly about?
正確答案：D
解析：題目詢問文章的主旨是什么。關鍵是要聽到文章開頭的三句話，由此可知D正確。主旨類題考查考生對短文的主題或主旨大意的概括理解，一般出現在短文的第一題或者最后一題。
30. Why can classical music play a positive role in problem solving?
正確答案：C
解析：題目詢問為什么古典音樂能夠在解決問題的過程中起到積極作用。關鍵是要聽到“（古典）音樂似乎刺激大腦里的神經活動”。故選C。符合短文聽力“聽到什么選什么”的原則。
31. What is one of the findings of the research?
正確答案：A
解析：題目詢問研究的發現之一是什么。關鍵是要聽到“你應該記住，刺激大腦的效果只能持續10-15分鐘。”故A正確而D錯誤。B中的Piano music應改成The less complex music，C未提及。