Question 21 is based on the passage you have just heard.

    If you are a graduate student, you may depend on your adviser for many things, including help with improving grades, acquiring financial support, forming an examining committee and getting letters of recommendation. If you‘re a graduate teaching assistant, your adviser also may be your boss. （19）Academic departments vary in their procedures for assigning academic advisers to graduate students. In some departments, either the chairman or the director of graduate studies serves for at least the first semester as a new student adviser. Then students select an adviser  based on shared academic interests. In other departments, a new student is assigned a faculty adviser based on some system of distribution of the department’s advising load. Later, students may have the opportunity of selecting the adviser that they prefer.（20）In any case, new graduate students can learn who their advisers or temporary advisers are by visiting or emailing the departmental office and asking for the information. （21）Graduation requirements specify the number of credits you must earn, the minimum grade point average you must achieve and the distribution of credits you must have from among differing departments or fields of study. In addition, it is necessary to apply for graduation when you are near the time that you will be completing your graduation requirements. Since graduation requirements vary among divisions of the university, you should consult the Bulletin of Information. You should also direct your questions to your departmental office or academic adviser.

21. What does the speaker say about graduation requirements?

本题为原文重现，上面一道题目的答案找到后，紧接着下一句就是这道题的答案，毕业要求详细说明了学生必须要获得的学生学分数，原文“Graduation requirements specify the number of credits you must earn,” B选项内容和原文基本一致，故正确答案为 B。