Normally a student must attend a certain number of courses in order to graduate, and each course that he attends gives him a credit, which he may count towards a degree. In many American universities the total work for a degree consists of thirty-six courses, each lasting for a term. A typical course consists of three classes per week for fifteen weeks; while attending a university a student will probably attend two terms a year. It is possible to spread a period of work for the degree over a longer period. It is also possible for a student to move between one university and another during his degree course, though this in fact is not done as a regular practice.       For every course that he follows a student is given a grade, which is recorded and available for the student to show employers. All this imposes a constant pressure and strain of study, but in spite of this some students still find time for great activities in student affairs. Elections to positions in the student union arouse great interests. Students who are qualified usually perform the effective work of the student union. With the big numbers of students, the operation of the system does involve a certain number of activities. A student who has held one of these positions in the union is much respected and it willbe of benefitto him. The  ed phrase "be of benefit" means   _  .
be demanding be pleasant be rewarding be considerate
Question: Normally a student must attend a certain number of courses in order to graduate, and each course that he attends gives him a credit, which he may count towards a degree. In many American universities the total work for a degree consists of thirty-six courses, each lasting for a term. A typical course consists of three classes per week for fifteen weeks; while attending a university a student will probably attend two terms a year. It is possible to spread a period of work for the degree over a longer period. It is also possible for a student to move between one university and another during his degree course, though this in fact is not done as a regular practice.       For every course that he follows a student is given a grade, which is recorded and available for the student to show employers. All this imposes a constant pressure and strain of study, but in spite of this some students still find time for great activities in student affairs. Elections to positions in the student union arouse great interests. Students who are qualified usually perform the effective work of the student union. With the big numbers of students, the operation of the system does involve a certain number of activities. A student who has held one of these positions in the union is much respected and it willbe of benefitto him. The  ed phrase "be of benefit" means   _  .
A. be demanding
B. be pleasant
C. be rewarding
D. be considerate
Answer: