题目：
Questions 24-30
·Look at the questions for this part.
·You will hear a passage about changes in the rankings of British universities.
·For questions 24-30, indicates which of the alternatives A, B, or C is the most appropriate response.
·Mark one letter A, B or C on the Answer Sheet.
How long has Harvard been at the top of the world ranking
A．For five years.
B．For three years.
C．For two years.
答案：
参考答案：A
解析：[听力原文] 24-30
British universities have slipped down the world rankings as they compete ever harder with eminent institutions overseas．Cambridge and Oxford have lost ground to Harvard and Yale while fewer British universities are in the top 200 list published today than last year．At a time when it is essential for British institutions to attract lucrative international students who pay higher fees，they are being outdone increasingly by American universities that receive huge endowments．Harvard tops the Times Higher Education-QS World University Rankings for the 5th consecutive year．Its endowment fund is greater than the total annual public funding for all universities in England．Yale holds the second spot after being jointly second with Cambridge and Oxford last year．The two British institutions came third and fourth respectively this year．4 British universities are in the top 10，the same as last year．Imperial College London fell from 5th to 6th place while University College London rose from 9th to 7th．In all，17 universities in Britain made it into the top l 00 List，down from 19 last year．More than a third of the top 100 are based in the U．S．Vice chancellors and commentators voiced concern that without an increase in investment，Britain’S standing as a first class destination for higher education could be under threat．The Times Higher Education-QS World University Rankings had 29 British university in the top 200，one fewer than last year．Of these，22 had slipped down the rankings． The rise of Asian institutions is reflected in the inclusion of 9 of them within the top 50， including 3 based in Hong Kong．2 new entrances this year are Hong Kong University of Science and Technology and Seoul National University．The rankings which are now in their 5th year are based on surveys of academics and graduate employers about which they consider the best universities in their field，the ratio of students to academics，the proportion of overseas students and staff at each university and the number of times research by each universities academics is quoted in other journals．
原文提到，哈佛大学连续5年雄踞排行榜榜首，所以答案是A。
