A、Because there are no signs to direct them. B、Because no tour guides are available. C、Because all the buildings in the city loo

"Where is the University?" is the question many visitors to Cambridge ask, but no one could point them in any one direction because there is no campus. The university consists of 31 self-governing colleges. [22]It has lecture halls, libraries, laboratories, museums and offices throughout the city.
    [23]Individual colleges choose their own students, who have to meet the minimum entrance requirements set by the university.
    Undergraduates usually live and study in their colleges, where they are taught in very small groups. Lectures and laboratory and practical work are organized by the university and held in university buildings.
    There are over 10,000 undergraduates and 3,500 postgraduates. About 40 percent of them are women and some 8 percent from overseas. As well as teaching, research is of major importance. Since the beginning of the 20th century, more than 60 university members have won Nobel Prizes.
    The university has a huge number of buildings for teaching and research. [24]It has more than 60 specialized subject libraries, as well as the University Library, which, as a copyright library, is entitled to a copy of every book published in Britain.
    Examinations are set and degrees are awarded by the university. [25]It allowed women to take the university exams in 1881, but it was not until 1948 that they were awarded degrees.
22. Why is it difficult for visitors to locate Cambridge University?
23. What does the passage tell us about the colleges of Cambridge University?
24. What can be learned from the passage about the libraries in Cambridge University?
25. What does the passage say about women students in Cambridge University?